에이전트 선택적 탐색 구조 개선과 경고 정리 반영

- claude-code 선택적 탐색 흐름을 참고해 Cowork/Code 시스템 프롬프트에서 folder_map 상시 선행 지시를 완화하고 glob/grep 기반 좁은 탐색을 우선하도록 조정함

- FolderMapTool 기본 depth를 2로, include_files 기본값을 false로 낮추고 MultiReadTool 최대 파일 수를 8개로 줄여 초기 과탐색 폭을 보수적으로 조정함

- AgentLoopExplorationPolicy partial을 추가해 탐색 범위 분류, broad-scan corrective hint, exploration_breadth 성능 로그를 연결함

- AgentLoopService에 탐색 범위 가이드 주입과 실행 중 탐색 폭 추적을 추가하고, 좁은 질문에서 반복적인 folder_map/대량 multi_read를 교정하도록 정리함

- DocxToHtmlConverter nullable 경고를 수정해 Release 빌드 경고 0 / 오류 0 기준을 다시 충족함

- README와 docs/DEVELOPMENT.md에 2026-04-09 10:36 (KST) 기준 개발 이력을 반영함

src/AxCopilot/Views/ChatWindow.AgentEventProcessor.cs

@@ -42,10 +42,30 @@ public partial class ChatWindow
 
     /// <summary>
     /// 에이전트 이벤트를 백그라운드 큐에 추가합니다.
-    /// 대화 변이(AppendExecutionEvent, AppendAgentRun)와 디스크 저장을 백그라운드에서 처리합니다.
+    /// ExecutionEvents는 UI 스레드에서 즉시 추가 (타임라인 렌더링 누락 방지).
+    /// 디스크 저장과 AgentRun 기록은 백그라운드에서 처리합니다.
     /// </summary>
     private void EnqueueAgentEventWork(AgentEvent evt, string eventTab, bool shouldRender)
     {
+        // ── 즉시 추가: ExecutionEvents에 동기적으로 반영 (RenderMessages 누락 방지) ──
+        try
+        {
+            lock (_convLock)
+            {
+                var session = _appState.ChatSession;
+                if (session != null)
+                {
+                    var result = _chatEngine.AppendExecutionEvent(
+                        session, null!, _currentConversation, _activeTab, eventTab, evt);
+                    _currentConversation = result.CurrentConversation;
+                }
+            }
+        }
+        catch (Exception ex)
+        {
+            LogService.Debug($"UI 스레드 이벤트 즉시 추가 실패: {ex.Message}");
+        }
+
         _agentEventChannel.Writer.TryWrite(new AgentEventWorkItem(evt, eventTab, _activeTab, shouldRender));
     }
 

src/AxCopilot/Views/ChatWindow.AgentEventRendering.cs

@@ -181,9 +181,9 @@ public partial class ChatWindow
         var msgMaxWidth = GetMessageMaxWidth();
         var stack = new StackPanel
         {
-            HorizontalAlignment = HorizontalAlignment.Center,
+            HorizontalAlignment = HorizontalAlignment.Left,
             MaxWidth = msgMaxWidth,
-            Margin = new Thickness(0),
+            Margin = new Thickness(48, 1, 12, 1),
         };
 
         var liveWaitingStyle = evt.Type == AgentEventType.Thinking
@@ -400,13 +400,12 @@ public partial class ChatWindow
 
         return new Border
         {
-            Background = cardBackground,
-            BorderBrush = cardBorder,
-            BorderThickness = new Thickness(1),
+            Background = Brushes.Transparent,
+            BorderThickness = new Thickness(0),
             CornerRadius = new CornerRadius(10),
-            Padding = new Thickness(10, 8, 10, 8),
-            Margin = new Thickness(12, 6, 12, 2),
-            HorizontalAlignment = HorizontalAlignment.Stretch,
+            Padding = new Thickness(0, 4, 0, 4),
+            Margin = new Thickness(0, 1, 12, 1),
+            HorizontalAlignment = HorizontalAlignment.Left,
             Child = contentGrid,
         };
     }
@@ -1186,6 +1185,30 @@ public partial class ChatWindow
             };
         }
 
+        // HTML/대용량 파일 내용이 이벤트 요약에 포함된 경우 인라인 표시 대신 1줄 요약으로 축소
+        if (!string.IsNullOrWhiteSpace(eventSummaryText) && evt.Type == AgentEventType.ToolResult
+            && eventSummaryText.Length > 500)
+        {
+            // HTML 내용 감지: <!DOCTYPE, <html, <head, <body, <div 등
+            var trimmed = eventSummaryText.TrimStart();
+            var firstLine = trimmed.Split('\n')[0];
+            if (trimmed.Contains("<!DOCTYPE", StringComparison.OrdinalIgnoreCase)
+                || trimmed.Contains("<html", StringComparison.OrdinalIgnoreCase)
+                || (evt.FilePath?.EndsWith(".html", StringComparison.OrdinalIgnoreCase) == true)
+                || (evt.FilePath?.EndsWith(".htm", StringComparison.OrdinalIgnoreCase) == true))
+            {
+                var lineCount = eventSummaryText.Count(c => c == '\n') + 1;
+                eventSummaryText = $"{firstLine}\n({lineCount}줄 · HTML 문서 — 미리보기 패널에서 확인)";
+            }
+            else if (eventSummaryText.Length > 2000)
+            {
+                // 기타 대용량 텍스트: 첫 3줄만 표시
+                var lines = eventSummaryText.Split('\n');
+                var preview = string.Join("\n", lines.Take(3));
+                eventSummaryText = preview + $"\n... ({lines.Length}줄 전체)";
+            }
+        }
+
         if (evt.Type == AgentEventType.StepStart && evt.StepTotal > 0)
             UpdateProgressBar(evt);
 
@@ -1204,13 +1227,12 @@ public partial class ChatWindow
         var bannerMaxWidth = GetMessageMaxWidth();
         var banner = new Border
         {
-            Background = hintBg,
-            BorderBrush = borderColor,
-            BorderThickness = new Thickness(1),
-            CornerRadius = new CornerRadius(10),
-            Padding = new Thickness(9, 7, 9, 7),
-            Margin = new Thickness(12, 3, 12, 3),
-            HorizontalAlignment = HorizontalAlignment.Center,
+            Background = Brushes.Transparent,
+            BorderThickness = new Thickness(0),
+            CornerRadius = new CornerRadius(8),
+            Padding = new Thickness(14, 5, 14, 5),
+            Margin = new Thickness(48, 1, 12, 1),
+            HorizontalAlignment = HorizontalAlignment.Left,
             MaxWidth = bannerMaxWidth,
         };
         if (!string.IsNullOrWhiteSpace(evt.RunId))

src/AxCopilot/Views/ChatWindow.ContextUsagePresentation.cs

@@ -33,12 +33,13 @@ public partial class ChatWindow
         var triggerRatio = triggerPercent / 100.0;
 
         // 메시지 토큰 추정: 메시지 수나 대화 ID가 바뀔 때만 재계산 (타이핑 중 반복 계산 방지)
+        // 스트리밍 중에는 매번 재계산 (도구 결과 메시지가 실시간으로 추가됨)
         int messageTokens;
         lock (_convLock)
         {
             var convId = _currentConversation?.Id;
             var msgCount = _currentConversation?.Messages?.Count ?? 0;
-            if (convId != _cachedConvIdForTokens || msgCount != _cachedMessageCountForTokens)
+            if (convId != _cachedConvIdForTokens || msgCount != _cachedMessageCountForTokens || _isStreaming)
             {
                 _cachedMessageTokens = msgCount > 0
                     ? Services.TokenEstimator.EstimateMessages(_currentConversation!.Messages)

src/AxCopilot/Views/ChatWindow.ConversationListPresentation.cs

@@ -16,6 +16,165 @@ public partial class ChatWindow
     private const int ConversationPageSize = 50;
     private List<ConversationMeta>? _pendingConversations;
 
+    // ── A-1: 이벤트 위임 필드 ──
+    /// <summary>현재 마우스가 올라가 있는 대화 항목 Border.</summary>
+    private Border? _lastHoveredConvBorder;
+    private bool _convPanelDelegationInitialized;
+
+    /// <summary>대화 항목 Border.Tag에 저장하는 메타 데이터.</summary>
+    private sealed class ConversationItemTag
+    {
+        public required string Id { get; init; }
+        public required bool IsSelected { get; init; }
+        public TextBlock? TitleBlock { get; init; }
+        public Brush? TitleColor { get; init; }
+        public Button? CatButton { get; init; }
+        public Brush? HoverBackground { get; init; }
+    }
+
+    /// <summary>ConversationPanel에 이벤트 위임 핸들러를 1회 등록합니다.</summary>
+    private void InitConversationPanelDelegation()
+    {
+        if (_convPanelDelegationInitialized || ConversationPanel == null)
+            return;
+        _convPanelDelegationInitialized = true;
+
+        ConversationPanel.MouseMove += ConversationPanel_DelegatedMouseMove;
+        ConversationPanel.MouseLeave += ConversationPanel_DelegatedMouseLeave;
+        ConversationPanel.PreviewMouseLeftButtonDown += ConversationPanel_DelegatedLeftButtonDown;
+        ConversationPanel.PreviewMouseRightButtonUp += ConversationPanel_DelegatedRightButtonUp;
+    }
+
+    private void ConversationPanel_DelegatedMouseMove(object sender, MouseEventArgs e)
+    {
+        var border = FindAncestorWithTag<Border>(e.OriginalSource as DependencyObject);
+        if (ReferenceEquals(border, _lastHoveredConvBorder))
+            return;
+
+        // 이전 호버 해제
+        if (_lastHoveredConvBorder?.Tag is ConversationItemTag prevTag)
+        {
+            if (!prevTag.IsSelected)
+                _lastHoveredConvBorder.Background = Brushes.Transparent;
+            if (prevTag.CatButton != null)
+                prevTag.CatButton.Visibility = Visibility.Collapsed;
+        }
+
+        _lastHoveredConvBorder = border;
+
+        // 새 호버 적용
+        if (border?.Tag is ConversationItemTag tag)
+        {
+            if (!tag.IsSelected)
+                border.Background = tag.HoverBackground ?? Brushes.Transparent;
+            if (tag.CatButton != null)
+                tag.CatButton.Visibility = Visibility.Visible;
+        }
+    }
+
+    private void ConversationPanel_DelegatedMouseLeave(object sender, MouseEventArgs e)
+    {
+        if (_lastHoveredConvBorder?.Tag is ConversationItemTag prevTag)
+        {
+            if (!prevTag.IsSelected)
+                _lastHoveredConvBorder.Background = Brushes.Transparent;
+            if (prevTag.CatButton != null)
+                prevTag.CatButton.Visibility = Visibility.Collapsed;
+        }
+        _lastHoveredConvBorder = null;
+    }
+
+    private void ConversationPanel_DelegatedLeftButtonDown(object sender, MouseButtonEventArgs e)
+    {
+        // catBtn Click은 자체 이벤트로 처리 — Button 내부 클릭이면 무시
+        if (FindAncestor<Button>(e.OriginalSource as DependencyObject) is not null)
+            return;
+
+        var border = FindAncestorWithTag<Border>(e.OriginalSource as DependencyObject);
+        if (border?.Tag is not ConversationItemTag tag)
+            return;
+
+        e.Handled = true;
+        HandleConversationItemClick(tag);
+    }
+
+    private void ConversationPanel_DelegatedRightButtonUp(object sender, MouseButtonEventArgs e)
+    {
+        var border = FindAncestorWithTag<Border>(e.OriginalSource as DependencyObject);
+        if (border?.Tag is not ConversationItemTag tag)
+            return;
+
+        e.Handled = true;
+        HandleConversationItemRightClick(tag);
+    }
+
+    private void HandleConversationItemClick(ConversationItemTag tag)
+    {
+        try
+        {
+            if (tag.IsSelected)
+            {
+                if (tag.TitleBlock != null && tag.TitleColor != null)
+                    EnterTitleEditMode(tag.TitleBlock, tag.Id, tag.TitleColor);
+                return;
+            }
+
+            if (_streamingTabs.Contains(_activeTab))
+            {
+                if (_tabStreamCts.TryGetValue(_activeTab, out var convListCts)) convListCts.Cancel();
+                _cursorTimer.Stop();
+                _typingTimer.Stop();
+                _elapsedTimer.Stop();
+                _activeStreamText = null;
+                _elapsedLabel = null;
+                _streamingTabs.Remove(_activeTab);
+                if (_tabStreamCts.Remove(_activeTab, out var removedCts)) removedCts.Dispose();
+            }
+
+            var conv = _storage.Load(tag.Id);
+            if (conv == null)
+                return;
+
+            lock (_convLock)
+            {
+                _currentConversation = ChatSession?.SetCurrentConversation(_activeTab, conv, _storage) ?? conv;
+                SyncTabConversationIdsFromSession();
+            }
+
+            SaveLastConversations();
+            UpdateChatTitle();
+            RenderMessages();
+            RefreshConversationList();
+            RefreshDraftQueueUi();
+        }
+        catch (Exception ex)
+        {
+            LogService.Error($"대화 전환 오류: {ex.Message}");
+        }
+    }
+
+    private void HandleConversationItemRightClick(ConversationItemTag tag)
+    {
+        if (!tag.IsSelected)
+        {
+            var conv = _storage.Load(tag.Id);
+            if (conv != null)
+            {
+                lock (_convLock)
+                {
+                    _currentConversation = ChatSession?.SetCurrentConversation(_activeTab, conv, _storage) ?? conv;
+                    SyncTabConversationIdsFromSession();
+                }
+                SaveLastConversations();
+                UpdateChatTitle();
+                RenderMessages();
+                RefreshDraftQueueUi();
+            }
+        }
+
+        Dispatcher.BeginInvoke(new Action(() => ShowConversationMenu(tag.Id)), DispatcherPriority.Input);
+    }
+
     public void RefreshConversationList()
     {
         var metas = _storage.LoadAllMeta();
@@ -66,20 +225,29 @@ public partial class ChatWindow
             };
         }).ToList();
 
-        items = items.Where(i => string.Equals(i.Tab, _activeTab, StringComparison.OrdinalIgnoreCase)).ToList();
+        // LINQ 체인을 한 번의 Where로 병합하여 중간 리스트 할당 제거
         items = items.Where(i =>
-            i.Pinned
-            || !string.IsNullOrWhiteSpace(i.ParentId)
-            || !string.Equals((i.Title ?? "").Trim(), "새 대화", StringComparison.OrdinalIgnoreCase)
-            || !string.IsNullOrWhiteSpace(i.Preview)
-            || i.AgentRunCount > 0
-            || i.FailedAgentRunCount > 0
-            || !string.Equals(i.Category, ChatCategory.General, StringComparison.OrdinalIgnoreCase)
+            string.Equals(i.Tab, _activeTab, StringComparison.OrdinalIgnoreCase)
+            && (i.Pinned
+                || !string.IsNullOrWhiteSpace(i.ParentId)
+                || !string.Equals((i.Title ?? "").Trim(), "새 대화", StringComparison.OrdinalIgnoreCase)
+                || !string.IsNullOrWhiteSpace(i.Preview)
+                || i.AgentRunCount > 0
+                || i.FailedAgentRunCount > 0
+                || !string.Equals(i.Category, ChatCategory.General, StringComparison.OrdinalIgnoreCase))
         ).ToList();
 
-        _failedConversationCount = items.Count(i => i.FailedAgentRunCount > 0);
-        _runningConversationCount = items.Count(i => i.IsRunning);
-        _spotlightConversationCount = items.Count(i => i.FailedAgentRunCount > 0 || i.AgentRunCount >= 3);
+        // Count를 한 번의 루프로 계산 (3번 순회 → 1번)
+        int failedCount = 0, runningCount = 0, spotlightCount = 0;
+        foreach (var i in items)
+        {
+            if (i.FailedAgentRunCount > 0) failedCount++;
+            if (i.IsRunning) runningCount++;
+            if (i.FailedAgentRunCount > 0 || i.AgentRunCount >= 3) spotlightCount++;
+        }
+        _failedConversationCount = failedCount;
+        _runningConversationCount = runningCount;
+        _spotlightConversationCount = spotlightCount;
         UpdateConversationFailureFilterUi();
         UpdateConversationRunningFilterUi();
         UpdateConversationQuickStripUi();
@@ -137,6 +305,7 @@ public partial class ChatWindow
 
     private void RenderConversationList(List<ConversationMeta> items)
     {
+        _lastHoveredConvBorder = null;
         ConversationPanel.Children.Clear();
         _pendingConversations = null;
 
@@ -211,6 +380,8 @@ public partial class ChatWindow
             Padding = new Thickness(8, 10, 8, 10),
             Margin = new Thickness(6, 4, 6, 4),
             HorizontalAlignment = HorizontalAlignment.Stretch,
+            // Tag를 설정하지 않아 이벤트 위임 대상에서 제외됨 (별도 핸들러)
+            Tag = new LoadMoreTag(),
         };
         var stack = new StackPanel { HorizontalAlignment = HorizontalAlignment.Center };
         stack.Children.Add(new TextBlock
@@ -238,6 +409,7 @@ public partial class ChatWindow
 
             var all = _pendingConversations;
             _pendingConversations = null;
+            _lastHoveredConvBorder = null;
             ConversationPanel.Children.Clear();
 
             string? lastGroup = null;
@@ -256,6 +428,9 @@ public partial class ChatWindow
         ConversationPanel.Children.Add(btn);
     }
 
+    /// <summary>"더 보기" 버튼의 Tag — ConversationItemTag와 구분하여 이벤트 위임에서 무시.</summary>
+    private sealed class LoadMoreTag;
+
     private static string GetConversationDateGroup(DateTime updatedAt)
     {
         var today = DateTime.Today;
@@ -440,85 +615,15 @@ public partial class ChatWindow
 
         border.Child = grid;
 
-        var hoverBg = new SolidColorBrush(Color.FromArgb(0x08, 0xFF, 0xFF, 0xFF));
-        border.MouseEnter += (_, _) =>
+        // A-1: 이벤트 위임 — 개별 람다 대신 Tag에 메타 저장, 부모에서 처리
+        border.Tag = new ConversationItemTag
         {
-            if (!isSelected)
-                border.Background = hoverBg;
-            catBtn.Visibility = Visibility.Visible;
-        };
-        border.MouseLeave += (_, _) =>
-        {
-            if (!isSelected)
-                border.Background = Brushes.Transparent;
-            catBtn.Visibility = Visibility.Collapsed;
-        };
-
-        border.MouseLeftButtonDown += (_, _) =>
-        {
-            try
-            {
-                if (isSelected)
-                {
-                    EnterTitleEditMode(title, item.Id, titleColor);
-                    return;
-                }
-
-                if (_streamingTabs.Contains(_activeTab))
-                {
-                    if (_tabStreamCts.TryGetValue(_activeTab, out var convListCts)) convListCts.Cancel();
-                    _cursorTimer.Stop();
-                    _typingTimer.Stop();
-                    _elapsedTimer.Stop();
-                    _activeStreamText = null;
-                    _elapsedLabel = null;
-                    _streamingTabs.Remove(_activeTab);
-                    if (_tabStreamCts.Remove(_activeTab, out var removedCts)) removedCts.Dispose();
-                }
-
-                var conv = _storage.Load(item.Id);
-                if (conv == null)
-                    return;
-
-                lock (_convLock)
-                {
-                    _currentConversation = ChatSession?.SetCurrentConversation(_activeTab, conv, _storage) ?? conv;
-                    SyncTabConversationIdsFromSession();
-                }
-
-                SaveLastConversations();
-                UpdateChatTitle();
-                RenderMessages();
-                RefreshConversationList();
-                RefreshDraftQueueUi();
-            }
-            catch (Exception ex)
-            {
-                LogService.Error($"대화 전환 오류: {ex.Message}");
-            }
-        };
-
-        border.MouseRightButtonUp += (_, me) =>
-        {
-            me.Handled = true;
-            if (!isSelected)
-            {
-                var conv = _storage.Load(item.Id);
-                if (conv != null)
-                {
-                    lock (_convLock)
-                    {
-                        _currentConversation = ChatSession?.SetCurrentConversation(_activeTab, conv, _storage) ?? conv;
-                        SyncTabConversationIdsFromSession();
-                    }
-                    SaveLastConversations();
-                    UpdateChatTitle();
-                    RenderMessages();
-                    RefreshDraftQueueUi();
-                }
-            }
-
-            Dispatcher.BeginInvoke(new Action(() => ShowConversationMenu(item.Id)), DispatcherPriority.Input);
+            Id = item.Id,
+            IsSelected = isSelected,
+            TitleBlock = title,
+            TitleColor = titleColor,
+            CatButton = catBtn,
+            HoverBackground = new SolidColorBrush(Color.FromArgb(0x08, 0xFF, 0xFF, 0xFF)),
         };
 
         ConversationPanel.Children.Add(border);

src/AxCopilot/Views/ChatWindow.FileBrowserPresentation.cs

@@ -62,9 +62,75 @@ public partial class ChatWindow
         FileBrowserPanel.Visibility = Visibility.Collapsed;
     }
 
+    // ── A-3: Clear 전 명시적 핸들러 해제 ──
+
+    /// <summary>TreeViewItem의 이벤트 핸들러를 재귀적으로 해제합니다.</summary>
+    private void DetachFileTreeHandlers(ItemCollection items)
+    {
+        foreach (var item in items.OfType<TreeViewItem>())
+        {
+            item.Expanded -= FileTreeItem_Expanded;
+            item.MouseDoubleClick -= FileTreeItem_DoubleClick;
+            item.MouseRightButtonUp -= FileTreeItem_RightClick;
+            DetachFileTreeHandlers(item.Items);
+        }
+    }
+
+    /// <summary>TreeViewItem의 깊이를 부모 탐색으로 계산합니다.</summary>
+    private static int GetTreeItemDepth(TreeViewItem item)
+    {
+        var depth = 0;
+        var parent = ItemsControl.ItemsControlFromItemContainer(item);
+        while (parent is TreeViewItem)
+        {
+            depth++;
+            parent = ItemsControl.ItemsControlFromItemContainer(parent);
+        }
+        return depth;
+    }
+
+    // ── 명명 핸들러 (람다 대체) ──
+
+    private void FileTreeItem_Expanded(object sender, RoutedEventArgs e)
+    {
+        if (sender is not TreeViewItem ti)
+            return;
+        if (ti.Items.Count != 1 || ti.Items[0] is not TreeViewItem placeholder || placeholder.Header?.ToString() != "로딩 중...")
+            return;
+
+        ti.Items.Clear();
+        if (ti.Tag is string dirPath && Directory.Exists(dirPath))
+        {
+            var depth = GetTreeItemDepth(ti);
+            var count = 0;
+            PopulateDirectory(new DirectoryInfo(dirPath), ti.Items, depth, ref count);
+        }
+    }
+
+    private void FileTreeItem_DoubleClick(object sender, MouseButtonEventArgs e)
+    {
+        e.Handled = true;
+        if (sender is TreeViewItem ti && ti.Tag is string path)
+            TryShowPreview(path);
+    }
+
+    private void FileTreeItem_RightClick(object sender, MouseButtonEventArgs e)
+    {
+        e.Handled = true;
+        if (sender is TreeViewItem ti)
+        {
+            ti.IsSelected = true;
+            if (ti.Tag is string path)
+                ShowFileTreeContextMenu(path);
+        }
+    }
+
     private void BuildFileTree()
     {
+        // A-3: Clear 전에 핸들러 명시적 해제 — 클로저 참조로 인한 GC 방해 방지
+        DetachFileTreeHandlers(FileTreeView.Items);
         FileTreeView.Items.Clear();
+
         var folder = GetCurrentWorkFolder();
         if (string.IsNullOrEmpty(folder) || !Directory.Exists(folder))
         {
@@ -102,17 +168,8 @@ public partial class ChatWindow
                 if (depth < 3)
                 {
                     dirItem.Items.Add(new TreeViewItem { Header = "로딩 중..." });
-                    var capturedDir = subDir;
-                    var capturedDepth = depth;
-                    dirItem.Expanded += (s, _) =>
-                    {
-                        if (s is TreeViewItem ti && ti.Items.Count == 1 && ti.Items[0] is TreeViewItem d && d.Header?.ToString() == "로딩 중...")
-                        {
-                            ti.Items.Clear();
-                            var c = 0;
-                            PopulateDirectory(capturedDir, ti.Items, capturedDepth + 1, ref c);
-                        }
-                    };
+                    // A-3: 명명 메서드 핸들러 — Tag에서 경로, GetTreeItemDepth()로 깊이 추출
+                    dirItem.Expanded += FileTreeItem_Expanded;
                 }
                 else
                 {
@@ -144,20 +201,9 @@ public partial class ChatWindow
                     Tag = file.FullName,
                 };
 
-                var capturedPath = file.FullName;
-                fileItem.MouseDoubleClick += (_, e) =>
-                {
-                    e.Handled = true;
-                    TryShowPreview(capturedPath);
-                };
-
-                fileItem.MouseRightButtonUp += (s, e) =>
-                {
-                    e.Handled = true;
-                    if (s is TreeViewItem ti)
-                        ti.IsSelected = true;
-                    ShowFileTreeContextMenu(capturedPath);
-                };
+                // A-3: 명명 메서드 핸들러 — Tag에서 경로 추출, 해제 가능
+                fileItem.MouseDoubleClick += FileTreeItem_DoubleClick;
+                fileItem.MouseRightButtonUp += FileTreeItem_RightClick;
 
                 items.Add(fileItem);
             }
@@ -310,12 +356,17 @@ public partial class ChatWindow
             return;
 
         _fileBrowserRefreshTimer?.Stop();
-        _fileBrowserRefreshTimer = new DispatcherTimer { Interval = TimeSpan.FromMilliseconds(500) };
-        _fileBrowserRefreshTimer.Tick += (_, _) =>
+        if (_fileBrowserRefreshTimer == null)
         {
-            _fileBrowserRefreshTimer.Stop();
-            BuildFileTree();
-        };
+            _fileBrowserRefreshTimer = new DispatcherTimer { Interval = TimeSpan.FromMilliseconds(500) };
+            _fileBrowserRefreshTimer.Tick += FileBrowserRefreshTimer_Tick;
+        }
         _fileBrowserRefreshTimer.Start();
     }
+
+    private void FileBrowserRefreshTimer_Tick(object? sender, EventArgs e)
+    {
+        _fileBrowserRefreshTimer?.Stop();
+        BuildFileTree();
+    }
 }

src/AxCopilot/Views/ChatWindow.GitBranchPresentation.cs

@@ -12,7 +12,7 @@ public partial class ChatWindow
 {
     private void UpdateGitBranchUi(string? branchName, string filesText, string addedText, string deletedText, string tooltip, Visibility visibility)
     {
-        Dispatcher.Invoke(() =>
+        _ = Dispatcher.InvokeAsync(() =>
         {
             _currentGitBranchName = branchName;
             _currentGitTooltip = tooltip;
@@ -152,9 +152,84 @@ public partial class ChatWindow
         if (BtnGitBranch == null)
             return;
 
-        await RefreshGitBranchStatusAsync();
-        BuildGitBranchPopup();
-        GitBranchPopup.IsOpen = true;
+        try
+        {
+            await RefreshGitBranchStatusAsync();
+            BuildGitBranchPopup();
+            GitBranchPopup.IsOpen = true;
+        }
+        catch (Exception ex)
+        {
+            Services.LogService.Error($"Git branch refresh failed: {ex.Message}");
+        }
+    }
+
+    // ── A-2: GitBranchItems 이벤트 위임 ──
+    private bool _gitBranchDelegationInitialized;
+    private Border? _lastHoveredGitBorder;
+
+    /// <summary>클릭 가능한 팝업 행의 Tag.</summary>
+    private sealed class PopupRowTag
+    {
+        public required Action OnClick { get; init; }
+        public required bool Selected { get; init; }
+        public Brush? HintBackground { get; init; }
+        public Brush? HoverBackground { get; init; }
+    }
+
+    private void InitGitBranchDelegation()
+    {
+        if (_gitBranchDelegationInitialized || GitBranchItems == null)
+            return;
+        _gitBranchDelegationInitialized = true;
+
+        GitBranchItems.MouseMove += GitBranch_DelegatedMouseMove;
+        GitBranchItems.MouseLeave += GitBranch_DelegatedMouseLeave;
+        GitBranchItems.PreviewMouseLeftButtonUp += GitBranch_DelegatedLeftButtonUp;
+        GitBranchItems.PreviewKeyDown += GitBranch_DelegatedKeyDown;
+    }
+
+    private void GitBranch_DelegatedMouseMove(object sender, MouseEventArgs e)
+    {
+        var border = FindAncestorWithTag<Border>(e.OriginalSource as DependencyObject);
+        if (ReferenceEquals(border, _lastHoveredGitBorder))
+            return;
+
+        if (_lastHoveredGitBorder?.Tag is PopupRowTag prevTag)
+            _lastHoveredGitBorder.Background = prevTag.Selected ? (prevTag.HintBackground ?? Brushes.Transparent) : Brushes.Transparent;
+        _lastHoveredGitBorder = border;
+
+        if (border?.Tag is PopupRowTag tag)
+            border.Background = tag.Selected ? (tag.HintBackground ?? Brushes.Transparent) : (tag.HoverBackground ?? Brushes.Transparent);
+    }
+
+    private void GitBranch_DelegatedMouseLeave(object sender, MouseEventArgs e)
+    {
+        if (_lastHoveredGitBorder?.Tag is PopupRowTag prevTag)
+            _lastHoveredGitBorder.Background = prevTag.Selected ? (prevTag.HintBackground ?? Brushes.Transparent) : Brushes.Transparent;
+        _lastHoveredGitBorder = null;
+    }
+
+    private void GitBranch_DelegatedLeftButtonUp(object sender, MouseButtonEventArgs e)
+    {
+        var border = FindAncestorWithTag<Border>(e.OriginalSource as DependencyObject);
+        if (border?.Tag is PopupRowTag tag)
+        {
+            e.Handled = true;
+            tag.OnClick();
+        }
+    }
+
+    private void GitBranch_DelegatedKeyDown(object sender, KeyEventArgs e)
+    {
+        if (e.Key is not (Key.Enter or Key.Space))
+            return;
+        var border = FindAncestorWithTag<Border>(e.OriginalSource as DependencyObject);
+        if (border?.Tag is PopupRowTag tag)
+        {
+            e.Handled = true;
+            tag.OnClick();
+        }
     }
 
     private void BuildGitBranchPopup()
@@ -162,6 +237,8 @@ public partial class ChatWindow
         if (GitBranchItems == null)
             return;
 
+        InitGitBranchDelegation();
+        _lastHoveredGitBorder = null;
         GitBranchItems.Children.Clear();
 
         var gitRoot = _currentGitRoot ?? ResolveGitRoot(GetCurrentWorkFolder());
@@ -462,18 +539,14 @@ public partial class ChatWindow
 
         border.Child = grid;
 
+        // A-2: 이벤트 위임 — 개별 람다 대신 Tag에 액션 저장, 부모에서 처리
         if (clickable && onClick != null)
         {
-            border.MouseEnter += (_, _) => border.Background = hoverBrush;
-            border.MouseLeave += (_, _) => border.Background = Brushes.Transparent;
-            border.MouseLeftButtonUp += (_, _) => onClick();
-            border.KeyDown += (_, keyEvent) =>
+            border.Tag = new PopupRowTag
             {
-                if (keyEvent.Key is Key.Enter or Key.Space)
-                {
-                    keyEvent.Handled = true;
-                    onClick();
-                }
+                OnClick = onClick,
+                Selected = false,
+                HoverBackground = hoverBrush,
             };
         }
 

src/AxCopilot/Views/ChatWindow.MessageBubblePresentation.cs

@@ -173,13 +173,11 @@ public partial class ChatWindow
 
         var contentCard = new Border
         {
-            BorderBrush = borderBrush,
-            BorderThickness = new Thickness(1),
-            CornerRadius = new CornerRadius(12),
-            Padding = new Thickness(11, 8, 11, 8),
+            Background = Brushes.Transparent,
+            BorderThickness = new Thickness(0),
+            CornerRadius = new CornerRadius(0),
+            Padding = new Thickness(2, 4, 2, 4),
         };
-        // DynamicResource 방식으로 바인딩 — 테마 전환 시 기존 버블도 자동 업데이트
-        contentCard.SetResourceReference(Border.BackgroundProperty, "ItemBackground");
         var contentStack = new StackPanel();
 
         var app = System.Windows.Application.Current as App;

src/AxCopilot/Views/ChatWindow.PermissionPresentation.cs

@@ -14,9 +14,91 @@ namespace AxCopilot.Views;
 
 public partial class ChatWindow
 {
+    // ── A-2: PermissionItems 이벤트 위임 ──
+    private bool _permPanelDelegationInitialized;
+
+    private sealed class PermissionItemTag
+    {
+        public required string Level { get; init; }
+        public required bool IsActive { get; init; }
+        public required Brush SelectedBackground { get; init; }
+        public required Brush HoverBackground { get; init; }
+    }
+
+    private void InitPermissionPanelDelegation()
+    {
+        if (_permPanelDelegationInitialized || PermissionItems == null)
+            return;
+        _permPanelDelegationInitialized = true;
+
+        PermissionItems.MouseMove += PermissionItems_DelegatedMouseMove;
+        PermissionItems.MouseLeave += PermissionItems_DelegatedMouseLeave;
+        PermissionItems.PreviewMouseLeftButtonDown += PermissionItems_DelegatedLeftButtonDown;
+        PermissionItems.PreviewKeyDown += PermissionItems_DelegatedKeyDown;
+    }
+
+    private Border? _lastHoveredPermBorder;
+
+    private void PermissionItems_DelegatedMouseMove(object sender, MouseEventArgs e)
+    {
+        var border = FindAncestorWithTag<Border>(e.OriginalSource as DependencyObject);
+        if (ReferenceEquals(border, _lastHoveredPermBorder))
+            return;
+
+        if (_lastHoveredPermBorder?.Tag is PermissionItemTag prevTag)
+            _lastHoveredPermBorder.Background = prevTag.IsActive ? prevTag.SelectedBackground : Brushes.Transparent;
+        _lastHoveredPermBorder = border;
+
+        if (border?.Tag is PermissionItemTag tag)
+            border.Background = tag.IsActive ? tag.SelectedBackground : tag.HoverBackground;
+    }
+
+    private void PermissionItems_DelegatedMouseLeave(object sender, MouseEventArgs e)
+    {
+        if (_lastHoveredPermBorder?.Tag is PermissionItemTag prevTag)
+            _lastHoveredPermBorder.Background = prevTag.IsActive ? prevTag.SelectedBackground : Brushes.Transparent;
+        _lastHoveredPermBorder = null;
+    }
+
+    private void PermissionItems_DelegatedLeftButtonDown(object sender, MouseButtonEventArgs e)
+    {
+        var border = FindAncestorWithTag<Border>(e.OriginalSource as DependencyObject);
+        if (border?.Tag is PermissionItemTag tag)
+        {
+            e.Handled = true;
+            ApplyPermissionLevel(tag.Level);
+        }
+    }
+
+    private void PermissionItems_DelegatedKeyDown(object sender, KeyEventArgs e)
+    {
+        if (e.Key is not (Key.Enter or Key.Space))
+            return;
+        var border = FindAncestorWithTag<Border>(e.OriginalSource as DependencyObject);
+        if (border?.Tag is PermissionItemTag tag)
+        {
+            e.Handled = true;
+            ApplyPermissionLevel(tag.Level);
+        }
+    }
+
+    private void ApplyPermissionLevel(string level)
+    {
+        _settings.Settings.Llm.FilePermission = PermissionModeCatalog.NormalizeGlobalMode(level);
+        try { _settings.Save(); } catch { }
+        _appState.LoadFromSettings(_settings);
+        UpdatePermissionUI();
+        SaveConversationSettings();
+        RefreshInlineSettingsPanel();
+        RefreshOverlayModeButtons();
+        PermissionPopup.IsOpen = false;
+    }
+
     private void BtnPermission_Click(object sender, RoutedEventArgs e)
     {
         if (PermissionPopup == null) return;
+        InitPermissionPanelDelegation();
+        _lastHoveredPermBorder = null;
         PermissionItems.Children.Clear();
 
         ChatConversation? currentConversation;
@@ -96,30 +178,14 @@ public partial class ChatWindow
                 row.Children.Add(check);
 
                 rowBorder.Child = row;
-                rowBorder.MouseEnter += (_, _) => rowBorder.Background = isActive ? selectedBackground : hoverBackground;
-                rowBorder.MouseLeave += (_, _) => rowBorder.Background = isActive ? selectedBackground : Brushes.Transparent;
 
-                var capturedLevel = level;
-                void ApplyPermission()
+                // A-2: 이벤트 위임 — 개별 람다 대신 Tag에 메타 저장
+                rowBorder.Tag = new PermissionItemTag
                 {
-                    _settings.Settings.Llm.FilePermission = PermissionModeCatalog.NormalizeGlobalMode(capturedLevel);
-                    try { _settings.Save(); } catch { }
-                    _appState.LoadFromSettings(_settings);
-                    UpdatePermissionUI();
-                    SaveConversationSettings();
-                    RefreshInlineSettingsPanel();
-                    RefreshOverlayModeButtons();
-                    PermissionPopup.IsOpen = false;
-                }
-
-                rowBorder.MouseLeftButtonDown += (_, _) => ApplyPermission();
-                rowBorder.KeyDown += (_, ke) =>
-                {
-                    if (ke.Key is Key.Enter or Key.Space)
-                    {
-                        ke.Handled = true;
-                        ApplyPermission();
-                    }
+                    Level = level,
+                    IsActive = isActive,
+                    SelectedBackground = selectedBackground,
+                    HoverBackground = hoverBackground,
                 };
 
                 container.Children.Add(rowBorder);

src/AxCopilot/Views/ChatWindow.PlanApprovalPresentation.cs

@@ -25,6 +25,12 @@ public partial class ChatWindow
                 _planViewerWindow?.LoadPlan(planSummary, steps, tcs);
                 ShowPlanButton(true);
                 AddDecisionButtons(tcs, options);
+                // 플랜 창 자동 표시 (사용자가 직접 BtnPlanViewer 클릭 안 해도 됨)
+                if (_planViewerWindow != null && IsWindowAlive(_planViewerWindow))
+                {
+                    _planViewerWindow.Show();
+                    _planViewerWindow.Activate();
+                }
             });
 
             var completed = await Task.WhenAny(tcs.Task, Task.Delay(TimeSpan.FromMinutes(5)));
@@ -88,61 +94,61 @@ public partial class ChatWindow
 
     private void ShowPlanButton(bool show)
     {
-        if (!show)
+        // 레거시: 이전 세션에서 동적 주입된 MoodIconPanel 칩 정리
+        try
         {
             for (int i = MoodIconPanel.Children.Count - 1; i >= 0; i--)
             {
                 if (MoodIconPanel.Children[i] is Border b && b.Tag?.ToString() == "PlanBtn")
                 {
-                    if (i > 0 && MoodIconPanel.Children[i - 1] is Border sep && sep.Tag?.ToString() == "PlanSep")
-                        MoodIconPanel.Children.RemoveAt(i - 1);
-                    if (i < MoodIconPanel.Children.Count)
-                        MoodIconPanel.Children.RemoveAt(Math.Min(i, MoodIconPanel.Children.Count - 1));
+                    // separator 먼저 제거 (인덱스 시프트 전)
+                    int sepIdx = i - 1;
+                    MoodIconPanel.Children.RemoveAt(i); // PlanBtn 제거
+                    if (sepIdx >= 0 && sepIdx < MoodIconPanel.Children.Count
+                        && MoodIconPanel.Children[sepIdx] is Border sep && sep.Tag?.ToString() == "PlanSep")
+                        MoodIconPanel.Children.RemoveAt(sepIdx);
                     break;
                 }
             }
+        }
+        catch
+        {
+            // 레거시 정리 실패 시에도 버튼 토글은 반드시 실행
+        }
+
+        // StatusBar의 XAML 선언 계획 버튼 토글
+        BtnPlanViewer.Visibility = show ? Visibility.Visible : Visibility.Collapsed;
+    }
+
+    private void BtnPlanViewer_Click(object sender, MouseButtonEventArgs e)
+    {
+        e.Handled = true;
+        if (string.IsNullOrWhiteSpace(_pendingPlanSummary) && _pendingPlanSteps.Count == 0)
             return;
-        }
 
-        foreach (var child in MoodIconPanel.Children)
+        EnsurePlanViewerWindow();
+        if (_planViewerWindow != null && IsWindowAlive(_planViewerWindow))
         {
-            if (child is Border b && b.Tag?.ToString() == "PlanBtn")
-                return;
-        }
-
-        var separator = new Border
-        {
-            Width = 1,
-            Height = 18,
-            Background = TryFindResource("SeparatorColor") as Brush ?? Brushes.Gray,
-            Margin = new Thickness(4, 0, 4, 0),
-            VerticalAlignment = VerticalAlignment.Center,
-            Tag = "PlanSep",
-        };
-        MoodIconPanel.Children.Add(separator);
-
-        var planBtn = CreateFolderBarButton("\uE9D2", "계획", "실행 계획 보기", "#10B981");
-        planBtn.Tag = "PlanBtn";
-        planBtn.MouseLeftButtonUp += (_, e) =>
-        {
-            e.Handled = true;
-            if (string.IsNullOrWhiteSpace(_pendingPlanSummary) && _pendingPlanSteps.Count == 0)
-                return;
-
-            EnsurePlanViewerWindow();
-            if (_planViewerWindow != null && IsWindowAlive(_planViewerWindow))
+            if (string.IsNullOrWhiteSpace(_planViewerWindow.PlanText)
+                || _planViewerWindow.PlanText != (_pendingPlanSummary ?? string.Empty)
+                || !_planViewerWindow.Steps.SequenceEqual(_pendingPlanSteps))
             {
-                if (string.IsNullOrWhiteSpace(_planViewerWindow.PlanText)
-                    || _planViewerWindow.PlanText != (_pendingPlanSummary ?? string.Empty)
-                    || !_planViewerWindow.Steps.SequenceEqual(_pendingPlanSteps))
-                {
-                    _planViewerWindow.LoadPlanPreview(_pendingPlanSummary ?? "", _pendingPlanSteps);
-                }
-                _planViewerWindow.Show();
-                _planViewerWindow.Activate();
+                _planViewerWindow.LoadPlanPreview(_pendingPlanSummary ?? "", _pendingPlanSteps);
             }
-        };
-        MoodIconPanel.Children.Add(planBtn);
+            _planViewerWindow.Show();
+            _planViewerWindow.Activate();
+        }
+    }
+
+    /// <summary>계획 버튼 호버 효과 초기화 (Loaded에서 호출).</summary>
+    private void InitPlanButtonHover()
+    {
+        var hoverBg = TryFindResource("ItemHoverBackground") as Brush
+                      ?? new SolidColorBrush(Color.FromArgb(0x18, 0xFF, 0xFF, 0xFF));
+        var normalBg = TryFindResource("HintBackground") as Brush ?? Brushes.Transparent;
+
+        BtnPlanViewer.MouseEnter += (_, _) => BtnPlanViewer.Background = hoverBg;
+        BtnPlanViewer.MouseLeave += (_, _) => BtnPlanViewer.Background = normalBg;
     }
 
     private void UpdatePlanViewerStep(AgentEvent evt)

src/AxCopilot/Views/ChatWindow.PreviewPresentation.cs

@@ -12,6 +12,7 @@ using System.Windows.Controls.Primitives;
 using System.Windows.Input;
 using System.Windows.Media;
 using System.Windows.Threading;
+using AxCopilot.Models;
 using AxCopilot.Services;
 
 namespace AxCopilot.Views;
@@ -21,6 +22,7 @@ public partial class ChatWindow
     private static readonly HashSet<string> _previewableExtensions = new(StringComparer.OrdinalIgnoreCase)
     {
         ".html", ".htm", ".md", ".txt", ".csv", ".json", ".xml", ".log",
+        ".docx", ".xlsx", ".pptx",
     };
 
     /// <summary>열려 있는 프리뷰 탭 목록 (파일 경로 기준).</summary>
@@ -29,6 +31,124 @@ public partial class ChatWindow
     private bool _webViewInitialized;
     private Popup? _previewTabPopup;
 
+    // ── A-2: PreviewTabPanel 이벤트 위임 ──
+    private bool _previewTabDelegationInitialized;
+    private Border? _lastHoveredPreviewTab;
+
+    private sealed class PreviewTabTag
+    {
+        public required string FilePath { get; init; }
+        public required bool IsActive { get; init; }
+        public Border? CloseButton { get; init; }
+    }
+
+    private void InitPreviewTabDelegation()
+    {
+        if (_previewTabDelegationInitialized || PreviewTabPanel == null)
+            return;
+        _previewTabDelegationInitialized = true;
+
+        PreviewTabPanel.MouseMove += PreviewTab_DelegatedMouseMove;
+        PreviewTabPanel.MouseLeave += PreviewTab_DelegatedMouseLeave;
+        PreviewTabPanel.PreviewMouseLeftButtonUp += PreviewTab_DelegatedLeftButtonUp;
+        PreviewTabPanel.PreviewMouseLeftButtonDown += PreviewTab_DelegatedLeftButtonDown;
+        PreviewTabPanel.PreviewMouseRightButtonUp += PreviewTab_DelegatedRightButtonUp;
+    }
+
+    private void PreviewTab_DelegatedMouseMove(object sender, MouseEventArgs e)
+    {
+        var border = FindAncestorWithTag<Border>(e.OriginalSource as DependencyObject);
+        if (ReferenceEquals(border, _lastHoveredPreviewTab))
+            return;
+
+        // 이전 호버 해제
+        if (_lastHoveredPreviewTab?.Tag is PreviewTabTag prevTag)
+        {
+            if (!prevTag.IsActive)
+            {
+                _lastHoveredPreviewTab.Background = Brushes.Transparent;
+                if (prevTag.CloseButton != null)
+                    prevTag.CloseButton.Visibility = Visibility.Hidden;
+            }
+        }
+
+        _lastHoveredPreviewTab = border;
+
+        // 새 호버 적용
+        if (border?.Tag is PreviewTabTag tag && !tag.IsActive)
+        {
+            border.Background = new SolidColorBrush(Color.FromArgb(0x10, 0xFF, 0xFF, 0xFF));
+            if (tag.CloseButton != null)
+                tag.CloseButton.Visibility = Visibility.Visible;
+        }
+    }
+
+    private void PreviewTab_DelegatedMouseLeave(object sender, MouseEventArgs e)
+    {
+        if (_lastHoveredPreviewTab?.Tag is PreviewTabTag prevTag && !prevTag.IsActive)
+        {
+            _lastHoveredPreviewTab.Background = Brushes.Transparent;
+            if (prevTag.CloseButton != null)
+                prevTag.CloseButton.Visibility = Visibility.Hidden;
+        }
+        _lastHoveredPreviewTab = null;
+    }
+
+    private void PreviewTab_DelegatedLeftButtonUp(object sender, MouseButtonEventArgs e)
+    {
+        // 닫기 버튼 클릭 여부 확인 (Tag == "close" 인 Border)
+        var closeAncestor = FindAncestor<Border>(e.OriginalSource as DependencyObject);
+        while (closeAncestor != null)
+        {
+            if (closeAncestor.Tag is string s && s == "close")
+            {
+                // 닫기 버튼 → 탭의 FilePath를 찾아 닫기
+                var tabBorder = FindAncestorWithTag<Border>(VisualTreeHelper.GetParent(closeAncestor));
+                if (tabBorder?.Tag is PreviewTabTag closeTag)
+                {
+                    e.Handled = true;
+                    ClosePreviewTab(closeTag.FilePath);
+                }
+                return;
+            }
+            if (closeAncestor.Tag is PreviewTabTag)
+                break;
+            var parent = VisualTreeHelper.GetParent(closeAncestor);
+            closeAncestor = parent as Border;
+        }
+
+        // 일반 탭 클릭
+        var border = FindAncestorWithTag<Border>(e.OriginalSource as DependencyObject);
+        if (border?.Tag is PreviewTabTag tag)
+        {
+            e.Handled = true;
+            _activePreviewTab = tag.FilePath;
+            RebuildPreviewTabs();
+            LoadPreviewContent(tag.FilePath);
+        }
+    }
+
+    private void PreviewTab_DelegatedLeftButtonDown(object sender, MouseButtonEventArgs e)
+    {
+        if (e.ClickCount != 2) return;
+        var border = FindAncestorWithTag<Border>(e.OriginalSource as DependencyObject);
+        if (border?.Tag is PreviewTabTag tag)
+        {
+            e.Handled = true;
+            OpenPreviewPopupWindow(tag.FilePath);
+        }
+    }
+
+    private void PreviewTab_DelegatedRightButtonUp(object sender, MouseButtonEventArgs e)
+    {
+        var border = FindAncestorWithTag<Border>(e.OriginalSource as DependencyObject);
+        if (border?.Tag is PreviewTabTag tag)
+        {
+            e.Handled = true;
+            ShowPreviewTabContextMenu(tag.FilePath);
+        }
+    }
+
     private static readonly string WebView2DataFolder =
         Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.ApplicationData),
                      "AxCopilot", "WebView2");
@@ -56,7 +176,9 @@ public partial class ChatWindow
 
         PreviewPanel.Visibility = Visibility.Visible;
         PreviewSplitter.Visibility = Visibility.Visible;
-        if (PreviewDot != null) PreviewDot.Fill = System.Windows.Media.Brushes.LimeGreen;
+        if (PreviewIcon != null)
+            PreviewIcon.Foreground = TryFindResource("AccentColor") as Brush ?? Brushes.LimeGreen;
+        UpdatePreviewChevronState();
 
         RebuildPreviewTabs();
         LoadPreviewContent(filePath);
@@ -64,6 +186,8 @@ public partial class ChatWindow
 
     private void RebuildPreviewTabs()
     {
+        InitPreviewTabDelegation();
+        _lastHoveredPreviewTab = null;
         PreviewTabPanel.Children.Clear();
 
         var accentBrush = TryFindResource("AccentColor") as Brush ?? Brushes.CornflowerBlue;
@@ -102,14 +226,6 @@ public partial class ChatWindow
             });
 
             var closeFg = isActive ? primaryText : secondaryText;
-            var closeBtnText = new TextBlock
-            {
-                Text = "\uE711",
-                FontFamily = new FontFamily("Segoe MDL2 Assets"),
-                FontSize = 10,
-                Foreground = closeFg,
-                VerticalAlignment = VerticalAlignment.Center,
-            };
             var closeBtn = new Border
             {
                 Background = Brushes.Transparent,
@@ -119,85 +235,30 @@ public partial class ChatWindow
                 Cursor = Cursors.Hand,
                 VerticalAlignment = VerticalAlignment.Center,
                 Visibility = isActive ? Visibility.Visible : Visibility.Hidden,
-                Child = closeBtnText,
+                Child = new TextBlock
+                {
+                    Text = "\uE711",
+                    FontFamily = new FontFamily("Segoe MDL2 Assets"),
+                    FontSize = 10,
+                    Foreground = closeFg,
+                    VerticalAlignment = VerticalAlignment.Center,
+                },
                 Tag = "close",
             };
 
-            var closePath = tabPath;
-            closeBtn.MouseEnter += (s, _) =>
-            {
-                if (s is Border b)
-                {
-                    b.Background = new SolidColorBrush(Color.FromArgb(0x40, 0xFF, 0x50, 0x50));
-                    if (b.Child is TextBlock tb)
-                        tb.Foreground = new SolidColorBrush(Color.FromRgb(0xFF, 0x60, 0x60));
-                }
-            };
-            closeBtn.MouseLeave += (s, _) =>
-            {
-                if (s is Border b)
-                {
-                    b.Background = Brushes.Transparent;
-                    if (b.Child is TextBlock tb)
-                        tb.Foreground = closeFg;
-                }
-            };
-            closeBtn.MouseLeftButtonUp += (_, e) =>
-            {
-                e.Handled = true;
-                ClosePreviewTab(closePath);
-            };
+            // closeBtn 호버 효과는 직접 이벤트 — 닫기 버튼은 수가 적고 탭에 종속
+            closeBtn.MouseEnter += CloseBtn_MouseEnter;
+            closeBtn.MouseLeave += CloseBtn_MouseLeave;
 
             tabContent.Children.Add(closeBtn);
             tabBorder.Child = tabContent;
 
-            var clickPath = tabPath;
-            tabBorder.MouseLeftButtonUp += (_, e) =>
+            // A-2: 이벤트 위임 — tabBorder의 클릭/호버는 PreviewTabPanel에서 처리
+            tabBorder.Tag = new PreviewTabTag
             {
-                if (e.Handled)
-                    return;
-
-                e.Handled = true;
-                _activePreviewTab = clickPath;
-                RebuildPreviewTabs();
-                LoadPreviewContent(clickPath);
-            };
-
-            var ctxPath = tabPath;
-            tabBorder.MouseRightButtonUp += (_, e) =>
-            {
-                e.Handled = true;
-                ShowPreviewTabContextMenu(ctxPath);
-            };
-
-            var dblPath = tabPath;
-            tabBorder.MouseLeftButtonDown += (_, e) =>
-            {
-                if (e.Handled)
-                    return;
-
-                if (e.ClickCount == 2)
-                {
-                    e.Handled = true;
-                    OpenPreviewPopupWindow(dblPath);
-                }
-            };
-
-            var capturedIsActive = isActive;
-            var capturedCloseBtn = closeBtn;
-            tabBorder.MouseEnter += (s, _) =>
-            {
-                if (s is Border b && !capturedIsActive)
-                    b.Background = new SolidColorBrush(Color.FromArgb(0x10, 0xFF, 0xFF, 0xFF));
-                if (!capturedIsActive)
-                    capturedCloseBtn.Visibility = Visibility.Visible;
-            };
-            tabBorder.MouseLeave += (s, _) =>
-            {
-                if (s is Border b && !capturedIsActive)
-                    b.Background = Brushes.Transparent;
-                if (!capturedIsActive)
-                    capturedCloseBtn.Visibility = Visibility.Hidden;
+                FilePath = tabPath,
+                IsActive = isActive,
+                CloseButton = closeBtn,
             };
 
             PreviewTabPanel.Children.Add(tabBorder);
@@ -216,6 +277,32 @@ public partial class ChatWindow
         }
     }
 
+    private static void CloseBtn_MouseEnter(object sender, MouseEventArgs e)
+    {
+        if (sender is Border b)
+        {
+            b.Background = new SolidColorBrush(Color.FromArgb(0x40, 0xFF, 0x50, 0x50));
+            if (b.Child is TextBlock tb)
+                tb.Foreground = new SolidColorBrush(Color.FromRgb(0xFF, 0x60, 0x60));
+        }
+    }
+
+    private static void CloseBtn_MouseLeave(object sender, MouseEventArgs e)
+    {
+        if (sender is Border b)
+        {
+            b.Background = Brushes.Transparent;
+            // closeFg는 탭마다 다르지만 기본 색상 복원
+            if (b.Child is TextBlock tb)
+                tb.Foreground = (TryFindResource("SecondaryText", b) as Brush) ?? Brushes.Gray;
+        }
+    }
+
+    private static Brush? TryFindResource(string key, DependencyObject element)
+    {
+        return element is FrameworkElement fe ? fe.TryFindResource(key) as Brush : null;
+    }
+
     private void ClosePreviewTab(string filePath)
     {
         _previewTabs.Remove(filePath);
@@ -279,6 +366,27 @@ public partial class ChatWindow
                     PreviewWebView.Visibility = Visibility.Visible;
                     break;
 
+                case ".docx":
+                    await EnsureWebViewInitializedAsync();
+                    var docxHtml = Services.Agent.DocxToHtmlConverter.Convert(filePath);
+                    PreviewWebView.NavigateToString(docxHtml);
+                    PreviewWebView.Visibility = Visibility.Visible;
+                    break;
+
+                case ".xlsx":
+                    await EnsureWebViewInitializedAsync();
+                    var xlsxHtml = Services.Agent.XlsxToHtmlConverter.Convert(filePath);
+                    PreviewWebView.NavigateToString(xlsxHtml);
+                    PreviewWebView.Visibility = Visibility.Visible;
+                    break;
+
+                case ".pptx":
+                    await EnsureWebViewInitializedAsync();
+                    var pptxHtml = Services.Agent.PptxToHtmlConverter.Convert(filePath);
+                    PreviewWebView.NavigateToString(pptxHtml);
+                    PreviewWebView.Visibility = Visibility.Visible;
+                    break;
+
                 case ".txt":
                 case ".json":
                 case ".xml":
@@ -347,6 +455,12 @@ public partial class ChatWindow
         catch (Exception ex)
         {
             LogService.Warn($"WebView2 초기화 실패: {ex.Message}");
+            // 사용자에게 피드백 — HTML 미리보기가 동작하지 않는 이유 안내
+            if (PreviewEmpty != null)
+            {
+                PreviewEmpty.Text = "WebView2 초기화 실패 — HTML 미리보기를 사용할 수 없습니다.\n외부 프로그램으로 열기를 이용하세요.";
+                PreviewEmpty.Visibility = System.Windows.Visibility.Visible;
+            }
         }
     }
 
@@ -434,7 +548,9 @@ public partial class ChatWindow
     {
         _previewTabs.Clear();
         _activePreviewTab = null;
-        if (PreviewDot != null) PreviewDot.Fill = System.Windows.Media.Brushes.Gray;
+        if (PreviewIcon != null)
+            PreviewIcon.Foreground = TryFindResource("SecondaryText") as Brush ?? Brushes.Gray;
+        UpdatePreviewChevronState();
         if (PreviewHeaderTitle != null) PreviewHeaderTitle.Text = "미리보기";
         if (PreviewHeaderSubtitle != null) PreviewHeaderSubtitle.Text = "선택한 파일이 여기에 표시됩니다";
         if (PreviewHeaderMeta != null) PreviewHeaderMeta.Text = "파일 메타";
@@ -470,15 +586,26 @@ public partial class ChatWindow
         // BtnPreviewToggle은 항상 표시 — 패널만 닫힘
     }
 
-    private void BtnPreviewToggle_Click(object sender, RoutedEventArgs e)
+    // ── 미리보기 Split Button 핸들러 ──
+
+    private void PreviewToggleArea_Click(object sender, MouseButtonEventArgs e)
     {
+        e.Handled = true;
+        TogglePreviewPanel();
+    }
+
+    private void TogglePreviewPanel()
+    {
+        var secondaryText = TryFindResource("SecondaryText") as Brush ?? Brushes.Gray;
+        var accentBrush = TryFindResource("AccentColor") as Brush ?? Brushes.LimeGreen;
+
         if (PreviewPanel.Visibility == Visibility.Visible)
         {
             PreviewPanel.Visibility = Visibility.Collapsed;
             PreviewSplitter.Visibility = Visibility.Collapsed;
             PreviewColumn.Width = new GridLength(0);
             SplitterColumn.Width = new GridLength(0);
-            if (PreviewDot != null) PreviewDot.Fill = System.Windows.Media.Brushes.Gray;
+            if (PreviewIcon != null) PreviewIcon.Foreground = secondaryText;
         }
         else if (_previewTabs.Count > 0)
         {
@@ -486,11 +613,130 @@ public partial class ChatWindow
             PreviewSplitter.Visibility = Visibility.Visible;
             PreviewColumn.Width = new GridLength(420);
             SplitterColumn.Width = new GridLength(5);
-            if (PreviewDot != null) PreviewDot.Fill = System.Windows.Media.Brushes.LimeGreen;
+            if (PreviewIcon != null) PreviewIcon.Foreground = accentBrush;
             RebuildPreviewTabs();
             if (_activePreviewTab != null)
                 LoadPreviewContent(_activePreviewTab);
         }
+        else
+        {
+            // 탭이 없을 때: 현재 대화에서 최근 생성 파일을 자동으로 찾아 열기
+            var recentFile = FindRecentPreviewableFile();
+            if (recentFile != null)
+                ShowPreviewPanel(recentFile);
+            else
+                ShowToast("미리보기할 파일이 없습니다. 작업 완료 후 다시 시도하세요.", "\uE7BA", 2000);
+        }
+    }
+
+    /// <summary>현재 대화의 ExecutionEvents에서 최근 미리보기 가능한 파일을 찾습니다.</summary>
+    private string? FindRecentPreviewableFile()
+    {
+        ChatConversation? conv;
+        lock (_convLock) conv = _currentConversation;
+        var events = conv?.ExecutionEvents;
+        if (events == null || events.Count == 0)
+            return null;
+
+        for (int i = events.Count - 1; i >= 0; i--)
+        {
+            var evt = events[i];
+            if (string.IsNullOrWhiteSpace(evt.FilePath))
+                continue;
+            var ext = System.IO.Path.GetExtension(evt.FilePath);
+            if (_previewableExtensions.Contains(ext))
+                return evt.FilePath;
+        }
+        return null;
+    }
+
+    private void PreviewChevron_Click(object sender, MouseButtonEventArgs e)
+    {
+        e.Handled = true;
+        if (_previewTabs.Count == 0) return;
+        ShowPreviewTabDropdown();
+    }
+
+    private Popup? _previewDropdownPopup;
+
+    private void ShowPreviewTabDropdown()
+    {
+        _previewDropdownPopup?.SetCurrentValue(Popup.IsOpenProperty, false);
+
+        var primaryText = TryFindResource("PrimaryText") as Brush ?? Brushes.White;
+        var secondaryText = TryFindResource("SecondaryText") as Brush ?? Brushes.Gray;
+        var accentBrush = TryFindResource("AccentColor") as Brush ?? Brushes.CornflowerBlue;
+
+        var stack = new StackPanel { Margin = new Thickness(2) };
+
+        foreach (var tabPath in _previewTabs)
+        {
+            var fileName = Path.GetFileName(tabPath);
+            var isActive = string.Equals(tabPath, _activePreviewTab, StringComparison.OrdinalIgnoreCase);
+            var ext = Path.GetExtension(tabPath).ToLowerInvariant();
+            var icon = ext switch
+            {
+                ".html" or ".htm" => "\uE8A7",
+                ".md" => "\uE8A5",
+                ".csv" => "\uE80A",
+                ".json" or ".xml" => "\uE943",
+                _ => "\uE8A5",
+            };
+            var capturedPath = tabPath;
+            var iconBrush = isActive ? accentBrush : secondaryText;
+            var textBrush = isActive ? primaryText : secondaryText;
+            var item = CreateSurfacePopupMenuItem(icon, iconBrush, fileName, () =>
+            {
+                _previewDropdownPopup!.IsOpen = false;
+                _activePreviewTab = capturedPath;
+                ShowPreviewPanel(capturedPath);
+            }, textBrush, 12.5);
+            stack.Children.Add(item);
+        }
+
+        var container = CreateSurfacePopupContainer(stack, 220, new Thickness(4, 6, 4, 6));
+        _previewDropdownPopup = new Popup
+        {
+            Child = container,
+            StaysOpen = false,
+            AllowsTransparency = true,
+            PopupAnimation = PopupAnimation.Fade,
+            Placement = PlacementMode.Bottom,
+            PlacementTarget = PreviewChevronArea,
+            VerticalOffset = 4,
+        };
+        _previewDropdownPopup.IsOpen = true;
+    }
+
+    /// <summary>셰브론 영역의 활성/비활성 상태를 _previewTabs 수에 맞춰 동기화.</summary>
+    private void UpdatePreviewChevronState()
+    {
+        if (PreviewChevronArea == null) return;
+        var hasItems = _previewTabs.Count > 0;
+        PreviewChevronArea.IsHitTestVisible = hasItems;
+        PreviewChevronArea.Opacity = hasItems ? 1.0 : 0.35;
+    }
+
+    /// <summary>미리보기 Split Button 호버 효과 초기화 (Loaded에서 호출).</summary>
+    private void InitPreviewSplitButtonHover()
+    {
+        var hoverBg = TryFindResource("ItemHoverBackground") as Brush
+                      ?? new SolidColorBrush(Color.FromArgb(0x18, 0xFF, 0xFF, 0xFF));
+
+        if (PreviewToggleArea != null)
+        {
+            PreviewToggleArea.MouseEnter += (_, _) => PreviewToggleArea.Background = hoverBg;
+            PreviewToggleArea.MouseLeave += (_, _) => PreviewToggleArea.Background = Brushes.Transparent;
+        }
+        if (PreviewChevronArea != null)
+        {
+            PreviewChevronArea.MouseEnter += (_, _) =>
+            {
+                if (PreviewChevronArea.IsHitTestVisible)
+                    PreviewChevronArea.Background = hoverBg;
+            };
+            PreviewChevronArea.MouseLeave += (_, _) => PreviewChevronArea.Background = Brushes.Transparent;
+        }
     }
 
     private void BtnOpenExternal_Click(object sender, RoutedEventArgs e)

src/AxCopilot/Views/ChatWindow.SelectionPopupPresentation.cs

@@ -176,9 +176,23 @@ public partial class ChatWindow
         }
 
         row.Child = grid;
+
+        // A-2: Tag 설정 — 위임이 있는 패널에서는 Tag 기반 처리
+        // 위임이 없는 패널에서는 아래 직접 핸들러가 동작
+        row.Tag = new PopupRowTag
+        {
+            OnClick = onClick ?? (() => { }),
+            Selected = selected,
+            HintBackground = hintBackground,
+            HoverBackground = hoverBackground,
+        };
+
+        // 직접 핸들러 — 위임 패널에서는 PreviewMouse*가 Handled=true로 설정하여 실행 안 됨
         row.MouseEnter += (_, _) => row.Background = selected ? hintBackground : hoverBackground;
         row.MouseLeave += (_, _) => row.Background = selected ? hintBackground : Brushes.Transparent;
-        row.MouseLeftButtonUp += (_, _) => onClick?.Invoke();
+        if (onClick != null)
+            row.MouseLeftButtonUp += (_, _) => onClick();
+
         return row;
     }
 }

src/AxCopilot/Views/ChatWindow.TopicPresetPresentation.cs

@@ -1,4 +1,4 @@
-using System;
+using System;
 using System.Linq;
 using System.Windows;
 using System.Windows.Controls;
@@ -12,9 +12,108 @@ namespace AxCopilot.Views;
 
 public partial class ChatWindow
 {
+    // ── A-1: TopicButtonPanel 이벤트 위임 ──
+    private Border? _lastHoveredTopicBorder;
+    private bool _topicPanelDelegationInitialized;
+
+    /// <summary>프리셋 카드 Border.Tag에 저장하는 메타 데이터.</summary>
+    private sealed class TopicCardTag
+    {
+        public required string Action { get; init; } // "preset" | "etc" | "add" | "custom_preset"
+        public TopicPreset? Preset { get; init; }
+        public required Brush NormalBackground { get; init; }
+        public required Brush HoverBackground { get; init; }
+        public Brush? NormalBorderBrush { get; init; }
+    }
+
+    /// <summary>TopicButtonPanel에 이벤트 위임 핸들러를 1회 등록합니다.</summary>
+    private void InitTopicPanelDelegation()
+    {
+        if (_topicPanelDelegationInitialized || TopicButtonPanel == null)
+            return;
+        _topicPanelDelegationInitialized = true;
+
+        TopicButtonPanel.Background = Brushes.Transparent; // 갭 영역도 히트테스트 대상으로 등록
+        TopicButtonPanel.MouseMove += TopicPanel_DelegatedMouseMove;
+        TopicButtonPanel.MouseLeave += TopicPanel_DelegatedMouseLeave;
+        TopicButtonPanel.PreviewMouseLeftButtonDown += TopicPanel_DelegatedLeftButtonDown;
+        TopicButtonPanel.PreviewMouseRightButtonUp += TopicPanel_DelegatedRightButtonUp;
+    }
+
+    private void TopicPanel_DelegatedMouseMove(object sender, MouseEventArgs e)
+    {
+        var border = FindAncestorWithTag<Border>(e.OriginalSource as DependencyObject);
+        if (ReferenceEquals(border, _lastHoveredTopicBorder))
+            return;
+
+        // 이전 호버 해제
+        if (_lastHoveredTopicBorder?.Tag is TopicCardTag prevTag)
+        {
+            _lastHoveredTopicBorder.Background = prevTag.NormalBackground;
+            if (prevTag.NormalBorderBrush != null)
+                _lastHoveredTopicBorder.BorderBrush = prevTag.NormalBorderBrush;
+        }
+
+        _lastHoveredTopicBorder = border;
+
+        // 새 호버 적용
+        if (border?.Tag is TopicCardTag tag)
+        {
+            border.Background = tag.HoverBackground;
+            border.BorderBrush = TryFindResource("AccentColor") as Brush ?? tag.NormalBorderBrush ?? border.BorderBrush;
+        }
+    }
+
+    private void TopicPanel_DelegatedMouseLeave(object sender, MouseEventArgs e)
+    {
+        if (_lastHoveredTopicBorder?.Tag is TopicCardTag prevTag)
+        {
+            _lastHoveredTopicBorder.Background = prevTag.NormalBackground;
+            if (prevTag.NormalBorderBrush != null)
+                _lastHoveredTopicBorder.BorderBrush = prevTag.NormalBorderBrush;
+        }
+        _lastHoveredTopicBorder = null;
+    }
+
+    private void TopicPanel_DelegatedLeftButtonDown(object sender, MouseButtonEventArgs e)
+    {
+        var border = FindAncestorWithTag<Border>(e.OriginalSource as DependencyObject);
+        if (border?.Tag is not TopicCardTag tag)
+            return;
+
+        e.Handled = true;
+        switch (tag.Action)
+        {
+            case "preset" or "custom_preset" when tag.Preset != null:
+                SelectTopic(tag.Preset);
+                break;
+            case "etc":
+                EmptyState.Visibility = Visibility.Collapsed;
+                InputBox.Focus();
+                break;
+            case "add":
+                ShowCustomPresetDialog();
+                break;
+        }
+    }
+
+    private void TopicPanel_DelegatedRightButtonUp(object sender, MouseButtonEventArgs e)
+    {
+        var border = FindAncestorWithTag<Border>(e.OriginalSource as DependencyObject);
+        if (border?.Tag is not TopicCardTag tag)
+            return;
+
+        if (tag.Action == "custom_preset" && tag.Preset != null)
+        {
+            e.Handled = true;
+            ShowCustomPresetContextMenu(border, tag.Preset);
+        }
+    }
+
     /// <summary>프리셋 대화 주제 버튼을 동적으로 생성합니다.</summary>
     private void BuildTopicButtons()
     {
+        _lastHoveredTopicBorder = null;
         TopicButtonPanel.Children.Clear();
         TopicButtonPanel.Visibility = Visibility.Visible;
         if (TopicPresetScrollViewer != null)
@@ -52,29 +151,8 @@ public partial class ChatWindow
         var primaryText = TryFindResource("PrimaryText") as Brush ?? Brushes.White;
         var secondaryText = TryFindResource("SecondaryText") as Brush ?? Brushes.Gray;
 
-        void AttachTopicCardHover(Border card, Brush normalBackground, Brush hoverBackground)
-        {
-            card.MouseEnter += (sender, _) =>
-            {
-                if (sender is Border hovered)
-                {
-                    hovered.Background = hoverBackground;
-                    hovered.BorderBrush = TryFindResource("AccentColor") as Brush ?? cardBorder;
-                }
-            };
-            card.MouseLeave += (sender, _) =>
-            {
-                if (sender is Border hovered)
-                {
-                    hovered.Background = normalBackground;
-                    hovered.BorderBrush = cardBorder;
-                }
-            };
-        }
-
         foreach (var preset in presets)
         {
-            var capturedPreset = preset;
             var buttonColor = BrushFromHex(preset.Color);
 
             var border = new Border
@@ -133,7 +211,7 @@ public partial class ChatWindow
 
             contentGrid.Children.Add(stack);
 
-            if (capturedPreset.IsCustom)
+            if (preset.IsCustom)
             {
                 var badge = new Border
                 {
@@ -158,17 +236,16 @@ public partial class ChatWindow
             }
 
             border.Child = contentGrid;
-            AttachTopicCardHover(border, cardBackground, cardHoverBackground);
-            border.MouseLeftButtonDown += (_, _) => SelectTopic(capturedPreset);
 
-            if (capturedPreset.IsCustom)
+            // A-1: 이벤트 위임 — 개별 람다 대신 Tag에 메타 저장
+            border.Tag = new TopicCardTag
             {
-                border.MouseRightButtonUp += (sender, args) =>
-                {
-                    args.Handled = true;
-                    ShowCustomPresetContextMenu(sender as Border, capturedPreset);
-                };
-            }
+                Action = preset.IsCustom ? "custom_preset" : "preset",
+                Preset = preset,
+                NormalBackground = cardBackground,
+                HoverBackground = cardHoverBackground,
+                NormalBorderBrush = cardBorder,
+            };
 
             TopicButtonPanel.Children.Add(border);
         }
@@ -225,11 +302,12 @@ public partial class ChatWindow
         });
         etcGrid.Children.Add(etcStack);
         etcBorder.Child = etcGrid;
-        AttachTopicCardHover(etcBorder, cardBackground, cardHoverBackground);
-        etcBorder.MouseLeftButtonDown += (_, _) =>
+        etcBorder.Tag = new TopicCardTag
         {
-            EmptyState.Visibility = Visibility.Collapsed;
-            InputBox.Focus();
+            Action = "etc",
+            NormalBackground = cardBackground,
+            HoverBackground = cardHoverBackground,
+            NormalBorderBrush = cardBorder,
         };
         TopicButtonPanel.Children.Add(etcBorder);
 
@@ -274,8 +352,13 @@ public partial class ChatWindow
 
         addGrid.Children.Add(addStack);
         addBorder.Child = addGrid;
-        AttachTopicCardHover(addBorder, Brushes.Transparent, cardHoverBackground);
-        addBorder.MouseLeftButtonDown += (_, _) => ShowCustomPresetDialog();
+        addBorder.Tag = new TopicCardTag
+        {
+            Action = "add",
+            NormalBackground = Brushes.Transparent,
+            HoverBackground = cardHoverBackground,
+            NormalBorderBrush = cardBorder,
+        };
         TopicButtonPanel.Children.Add(addBorder);
 
         UpdateTopicPresetScrollMode();

src/AxCopilot/Views/ChatWindow.TranscriptRenderExecution.cs

@@ -1,7 +1,81 @@
+using System.Collections.Generic;
+
 namespace AxCopilot.Views;
 
 public partial class ChatWindow
 {
+    /// <summary>
+    /// B-3: 스트리밍 전용 append-only 렌더 경로.
+    /// prefix 비교를 완전히 우회하고, stable 키의 부분집합 관계만 확인하여
+    /// 새 항목만 추가하는 빠른 경로. B-1/B-2로 인크리멘탈이 대부분 성공하지만,
+    /// 스트리밍 중 키 순서가 변경되는 극단적 경우에도 전체 재빌드를 방지합니다.
+    /// </summary>
+    private bool TryApplyStreamingAppendRender(TranscriptRenderPlan renderPlan)
+    {
+        if (!_isStreaming || _lastRenderedTimelineKeys.Count == 0 || renderPlan.NewKeys.Count == 0)
+            return false;
+
+        // hiddenCount가 다르면 visible 범위 자체가 달라진 것 — append 불가
+        if (renderPlan.HiddenCount != _lastRenderedHiddenCount)
+            return false;
+
+        // 기존 stable 키가 새 키 집합의 부분집합인지 확인 (순서 무관)
+        var previousStable = new HashSet<string>(StringComparer.Ordinal);
+        foreach (var key in _lastRenderedTimelineKeys)
+        {
+            if (!key.StartsWith("_live_", StringComparison.Ordinal))
+                previousStable.Add(key);
+        }
+
+        var newStableSet = new HashSet<string>(StringComparer.Ordinal);
+        foreach (var key in renderPlan.NewKeys)
+        {
+            if (!key.StartsWith("_live_", StringComparison.Ordinal))
+                newStableSet.Add(key);
+        }
+
+        if (!previousStable.IsSubsetOf(newStableSet))
+            return false;
+
+        try
+        {
+            // 라이브 컨테이너 임시 분리
+            var hadLiveContainer = _agentLiveContainer != null && ContainsTranscriptElement(_agentLiveContainer);
+            if (hadLiveContainer)
+                RemoveTranscriptElement(_agentLiveContainer!);
+
+            // 기존 live 항목 제거 (끝에서부터)
+            for (var i = _lastRenderedTimelineKeys.Count - 1; i >= 0; i--)
+            {
+                if (!_lastRenderedTimelineKeys[i].StartsWith("_live_", StringComparison.Ordinal))
+                    break;
+                if (GetTranscriptElementCount() > 0)
+                    RemoveTranscriptElementAt(GetTranscriptElementCount() - 1);
+            }
+
+            // 새로 추가된 항목만 렌더 (기존에 없던 키)
+            foreach (var item in renderPlan.VisibleTimeline)
+            {
+                if (!previousStable.Contains(item.Key))
+                    item.Render();
+            }
+
+            // 라이브 컨테이너 재삽입
+            if (hadLiveContainer && _agentLiveContainer != null)
+                AddTranscriptElement(_agentLiveContainer);
+
+            _lastRenderedTimelineKeys = renderPlan.NewKeys;
+            _lastRenderedHiddenCount = renderPlan.HiddenCount;
+            return true;
+        }
+        catch (Exception ex)
+        {
+            Services.LogService.Warn($"스트리밍 append 렌더 실패, 전체 렌더로 전환: {ex.Message}");
+            _lastRenderedTimelineKeys.Clear();
+            return false;
+        }
+    }
+
     private bool TryApplyIncrementalTranscriptRender(TranscriptRenderPlan renderPlan)
     {
         if (!renderPlan.CanIncremental)
@@ -22,12 +96,21 @@ public partial class ChatWindow
 
         try
         {
+            // B-2: 라이브 컨테이너가 transcript 끝에 있으면 임시 분리
+            var hadLiveContainer = _agentLiveContainer != null && ContainsTranscriptElement(_agentLiveContainer);
+            if (hadLiveContainer)
+                RemoveTranscriptElement(_agentLiveContainer!);
+
             for (var removeIndex = 0; removeIndex < renderPlan.PreviousLiveCount && GetTranscriptElementCount() > 0; removeIndex++)
                 RemoveTranscriptElementAt(GetTranscriptElementCount() - 1);
 
             for (var i = renderPlan.PreviousStableCount; i < renderPlan.VisibleTimeline.Count; i++)
                 renderPlan.VisibleTimeline[i].Render();
 
+            // B-2: 라이브 컨테이너 재삽입
+            if (hadLiveContainer && _agentLiveContainer != null)
+                AddTranscriptElement(_agentLiveContainer);
+
             _lastRenderedTimelineKeys = renderPlan.NewKeys;
             _lastRenderedHiddenCount = renderPlan.HiddenCount;
             return true;

src/AxCopilot/Views/ChatWindow.TranscriptRenderPlanner.cs

@@ -23,6 +23,13 @@ public partial class ChatWindow
         var orderedTimeline = BuildTimelineRenderActions(visibleMessages, visibleEvents);
         var effectiveRenderLimit = GetActiveTimelineRenderLimit();
         var hiddenCount = Math.Max(0, orderedTimeline.Count - effectiveRenderLimit);
+
+        // B-1: 스트리밍 중 hiddenCount 안정화 — 감소만 차단하여 prefix 키 불일치 방지
+        // 스트리밍 시 GetActiveTimelineRenderLimit()가 더 작은 값을 반환하면
+        // hiddenCount가 변동하여 visible 범위가 밀리고 인크리멘탈 렌더가 항상 실패함
+        if (_isStreaming && _lastRenderedHiddenCount >= 0 && hiddenCount < _lastRenderedHiddenCount)
+            hiddenCount = _lastRenderedHiddenCount;
+
         var visibleTimeline = hiddenCount > 0
             ? orderedTimeline.GetRange(hiddenCount, orderedTimeline.Count - hiddenCount)
             : orderedTimeline;
@@ -31,10 +38,14 @@ public partial class ChatWindow
         foreach (var item in visibleTimeline)
             newKeys.Add(item.Key);
 
-        var hasExternalChildren = _agentLiveContainer != null && ContainsTranscriptElement(_agentLiveContainer);
-        var expectedChildCount = _lastRenderedTimelineKeys.Count + (_lastRenderedHiddenCount > 0 ? 1 : 0);
-        var canIncremental = !hasExternalChildren
-            && _lastRenderedTimelineKeys.Count > 0
+        // B-2: _agentLiveContainer가 transcript에 있어도 인크리멘탈 허용
+        // 라이브 컨테이너는 인크리멘탈 렌더 시 임시 분리 후 재삽입하므로
+        // expectedChildCount에 포함하고 canIncremental 조건에서 제외
+        var liveContainerInTranscript = _agentLiveContainer != null && ContainsTranscriptElement(_agentLiveContainer);
+        var expectedChildCount = _lastRenderedTimelineKeys.Count
+            + (_lastRenderedHiddenCount > 0 ? 1 : 0)
+            + (liveContainerInTranscript ? 1 : 0);
+        var canIncremental = _lastRenderedTimelineKeys.Count > 0
             && newKeys.Count >= _lastRenderedTimelineKeys.Count
             && _lastRenderedHiddenCount == hiddenCount
             && GetTranscriptElementCount() == expectedChildCount;

src/AxCopilot/Views/ChatWindow.TranscriptRendering.cs

@@ -20,6 +20,10 @@ public partial class ChatWindow
 
     private void RenderMessages(bool preserveViewport = false)
     {
+        // B-4: 비가시 상태일 때 렌더링 차단 — 최소화/숨김 시 불필요한 UI 재구축 방지
+        if (this.WindowState == System.Windows.WindowState.Minimized || !IsVisible)
+            return;
+
         var renderStopwatch = Stopwatch.StartNew();
         var previousScrollableHeight = GetTranscriptScrollableHeight();
         var previousVerticalOffset = GetTranscriptVerticalOffset();
@@ -63,7 +67,9 @@ public partial class ChatWindow
         EmptyState.Visibility = System.Windows.Visibility.Collapsed;
         var renderPlan = BuildTranscriptRenderPlan(conv, visibleMessages, visibleEvents);
 
-        if (!TryApplyIncrementalTranscriptRender(renderPlan))
+        // B-3: 스트리밍 전용 빠른 경로 → 일반 인크리멘탈 → 전체 재빌드
+        if (!TryApplyStreamingAppendRender(renderPlan)
+            && !TryApplyIncrementalTranscriptRender(renderPlan))
             ApplyFullTranscriptRender(renderPlan);
         PruneTranscriptElementCache(renderPlan.NewKeys);
 

src/AxCopilot/Views/ChatWindow.TranscriptVirtualization.cs

@@ -4,15 +4,19 @@ namespace AxCopilot.Views;
 
 public partial class ChatWindow
 {
-    private const int TranscriptCacheRetentionCount = 240;
+    /// <summary>최대 캐시 보유 수. 화면 표시 항목 + 여유분.</summary>
+    private const int TranscriptCacheRetentionCount = 120;
 
     private void PruneTranscriptElementCache(IReadOnlyCollection<string> visibleKeys)
     {
-        if (_elementCache.Count <= TranscriptCacheRetentionCount)
+        // 캐시가 보유 한도의 1.5배 이상일 때만 정리 (빈번한 정리 방지)
+        if (_elementCache.Count <= TranscriptCacheRetentionCount * 3 / 2)
             return;
 
         var keep = new HashSet<string>(visibleKeys, StringComparer.Ordinal);
-        foreach (var key in _lastRenderedTimelineKeys.TakeLast(Math.Min(TranscriptCacheRetentionCount, _lastRenderedTimelineKeys.Count)))
+        // 최근 렌더링된 키 중 보유 한도만큼만 유지
+        var retainFromRendered = Math.Min(TranscriptCacheRetentionCount, _lastRenderedTimelineKeys.Count);
+        foreach (var key in _lastRenderedTimelineKeys.TakeLast(retainFromRendered))
             keep.Add(key);
 
         var removable = _elementCache.Keys

src/AxCopilot/Views/ChatWindow.UserAskPresentation.cs

@@ -51,185 +51,236 @@ public partial class ChatWindow
                      ?? new SolidColorBrush(Color.FromArgb(0x10, accentColor.R, accentColor.G, accentColor.B));
         var hoverBg = TryFindResource("ItemHoverBackground") as Brush
                       ?? new SolidColorBrush(Color.FromArgb(0x16, 0xFF, 0xFF, 0xFF));
-        var okBrush = BrushFromHex("#10B981");
-        var dangerBrush = BrushFromHex("#EF4444");
+        var selectedBg = new SolidColorBrush(Color.FromArgb(0x20, accentColor.R, accentColor.G, accentColor.B));
 
         var container = new Border
         {
-            Margin = new Thickness(40, 4, 90, 8),
-            HorizontalAlignment = HorizontalAlignment.Left,
-            MaxWidth = Math.Max(420, GetMessageMaxWidth() - 36),
+            Margin = new Thickness(48, 6, 48, 10),
+            HorizontalAlignment = HorizontalAlignment.Stretch,
+            MaxWidth = Math.Max(540, GetMessageMaxWidth()),
             Background = itemBg,
             BorderBrush = borderBrush,
             BorderThickness = new Thickness(1),
-            CornerRadius = new CornerRadius(14),
-            Padding = new Thickness(14, 12, 14, 12),
+            CornerRadius = new CornerRadius(16),
+            Padding = new Thickness(20, 18, 20, 18),
         };
 
         var outer = new StackPanel();
-        outer.Children.Add(new TextBlock
-        {
-            Text = "의견 요청",
-            FontSize = 12.5,
-            FontWeight = FontWeights.SemiBold,
-            Foreground = primaryText,
-        });
+
+        // ── 질문 텍스트 ──
         outer.Children.Add(new TextBlock
         {
             Text = question,
-            Margin = new Thickness(0, 4, 0, 10),
-            FontSize = 12.5,
+            FontSize = 14,
             Foreground = primaryText,
             TextWrapping = TextWrapping.Wrap,
-            LineHeight = 20,
+            LineHeight = 22,
+            Margin = new Thickness(0, 0, 0, 14),
         });
 
-        Border? selectedOption = null;
+        // ── 옵션 카드 목록 ──
+        Border? selectedCard = null;
+        TextBox? customInputBox = null;
         string selectedResponse = defaultValue;
 
+        var cardPanel = new StackPanel { Margin = new Thickness(0, 0, 0, 4) };
+
         if (options.Count > 0)
         {
-            var optionPanel = new WrapPanel
+            for (int i = 0; i < options.Count; i++)
             {
-                Margin = new Thickness(0, 0, 0, 10),
-                ItemWidth = double.NaN,
-            };
+                var optionLabel = options[i].Trim();
+                if (string.IsNullOrWhiteSpace(optionLabel)) continue;
+                var optionNumber = i + 1;
 
-            foreach (var option in options.Where(static option => !string.IsNullOrWhiteSpace(option)))
-            {
-                var optionLabel = option.Trim();
-                var optBorder = new Border
+                var card = new Border
                 {
                     Background = Brushes.Transparent,
                     BorderBrush = borderBrush,
                     BorderThickness = new Thickness(1),
-                    CornerRadius = new CornerRadius(999),
-                    Padding = new Thickness(10, 6, 10, 6),
-                    Margin = new Thickness(0, 0, 8, 8),
+                    CornerRadius = new CornerRadius(10),
+                    Padding = new Thickness(14, 10, 14, 10),
+                    Margin = new Thickness(0, 0, 0, 6),
                     Cursor = Cursors.Hand,
+                };
+
+                var cardGrid = new Grid();
+                cardGrid.ColumnDefinitions.Add(new ColumnDefinition { Width = new GridLength(1, GridUnitType.Star) });
+                cardGrid.ColumnDefinitions.Add(new ColumnDefinition { Width = GridLength.Auto });
+
+                var textStack = new StackPanel();
+                textStack.Children.Add(new TextBlock
+                {
+                    Text = optionLabel,
+                    FontSize = 13,
+                    FontWeight = FontWeights.SemiBold,
+                    Foreground = primaryText,
+                    TextWrapping = TextWrapping.Wrap,
+                });
+                Grid.SetColumn(textStack, 0);
+                cardGrid.Children.Add(textStack);
+
+                // 번호 배지
+                var badge = new Border
+                {
+                    Width = 24, Height = 24,
+                    CornerRadius = new CornerRadius(12),
+                    Background = new SolidColorBrush(Color.FromArgb(0x20, 0xFF, 0xFF, 0xFF)),
+                    VerticalAlignment = VerticalAlignment.Center,
                     Child = new TextBlock
                     {
-                        Text = optionLabel,
-                        FontSize = 12,
-                        Foreground = primaryText,
+                        Text = optionNumber.ToString(),
+                        FontSize = 11,
+                        FontWeight = FontWeights.Bold,
+                        Foreground = secondaryText,
+                        HorizontalAlignment = HorizontalAlignment.Center,
+                        VerticalAlignment = VerticalAlignment.Center,
                     },
                 };
+                Grid.SetColumn(badge, 1);
+                cardGrid.Children.Add(badge);
 
-                optBorder.MouseEnter += (s, _) =>
+                card.Child = cardGrid;
+
+                var capturedLabel = optionLabel;
+                var capturedCard = card;
+                card.MouseEnter += (_, _) =>
                 {
-                    if (!ReferenceEquals(selectedOption, s))
-                        ((Border)s).Background = hoverBg;
+                    if (!ReferenceEquals(selectedCard, capturedCard))
+                        capturedCard.Background = hoverBg;
                 };
-                optBorder.MouseLeave += (s, _) =>
+                card.MouseLeave += (_, _) =>
                 {
-                    if (!ReferenceEquals(selectedOption, s))
-                        ((Border)s).Background = Brushes.Transparent;
+                    if (!ReferenceEquals(selectedCard, capturedCard))
+                        capturedCard.Background = Brushes.Transparent;
                 };
-                optBorder.MouseLeftButtonUp += (_, _) =>
+                card.MouseLeftButtonUp += (_, _) =>
                 {
-                    if (selectedOption != null)
+                    // 이전 선택 해제
+                    if (selectedCard != null)
                     {
-                        selectedOption.Background = Brushes.Transparent;
-                        selectedOption.BorderBrush = borderBrush;
+                        selectedCard.Background = Brushes.Transparent;
+                        selectedCard.BorderBrush = borderBrush;
                     }
+                    // 커스텀 입력 카드 선택 해제
+                    if (customInputBox != null)
+                        customInputBox.BorderBrush = borderBrush;
 
-                    selectedOption = optBorder;
-                    selectedOption.Background = new SolidColorBrush(Color.FromArgb(0x18, accentColor.R, accentColor.G, accentColor.B));
-                    selectedOption.BorderBrush = accentBrush;
-                    selectedResponse = optionLabel;
+                    selectedCard = capturedCard;
+                    selectedCard.Background = selectedBg;
+                    selectedCard.BorderBrush = accentBrush;
+                    selectedResponse = capturedLabel;
                 };
 
-                optionPanel.Children.Add(optBorder);
+                cardPanel.Children.Add(card);
             }
-
-            outer.Children.Add(optionPanel);
         }
 
-        outer.Children.Add(new TextBlock
+        // ── 마지막 카드: 직접 입력 (Claude Desktop 스타일) ──
+        var customCard = new Border
         {
-            Text = "직접 입력",
-            FontSize = 11.5,
-            Foreground = secondaryText,
+            Background = Brushes.Transparent,
+            BorderBrush = borderBrush,
+            BorderThickness = new Thickness(1),
+            CornerRadius = new CornerRadius(10),
+            Padding = new Thickness(2),
             Margin = new Thickness(0, 0, 0, 6),
-        });
+        };
 
-        var inputBox = new TextBox
+        customInputBox = new TextBox
         {
             Text = defaultValue,
             AcceptsReturn = true,
             TextWrapping = TextWrapping.Wrap,
-            MinHeight = 42,
-            MaxHeight = 100,
-            FontSize = 12.5,
-            Padding = new Thickness(10, 8, 10, 8),
+            MinHeight = 38,
+            MaxHeight = 120,
+            FontSize = 13,
+            Padding = new Thickness(12, 8, 12, 8),
             Background = Brushes.Transparent,
             Foreground = primaryText,
             CaretBrush = primaryText,
-            BorderBrush = borderBrush,
-            BorderThickness = new Thickness(1),
+            BorderThickness = new Thickness(0),
         };
-        inputBox.TextChanged += (_, _) =>
+        // 플레이스홀더
+        if (string.IsNullOrWhiteSpace(defaultValue))
         {
-            if (!string.IsNullOrWhiteSpace(inputBox.Text))
+            customInputBox.Tag = "placeholder";
+            customInputBox.Text = "직접 입력...";
+            customInputBox.Foreground = secondaryText;
+        }
+        customInputBox.GotFocus += (_, _) =>
+        {
+            if (customInputBox.Tag?.ToString() == "placeholder")
             {
-                selectedResponse = inputBox.Text.Trim();
-                if (selectedOption != null)
-                {
-                    selectedOption.Background = Brushes.Transparent;
-                    selectedOption.BorderBrush = borderBrush;
-                    selectedOption = null;
-                }
+                customInputBox.Text = "";
+                customInputBox.Foreground = primaryText;
+                customInputBox.Tag = null;
             }
+            // 옵션 카드 선택 해제 + 커스텀 카드 활성화
+            if (selectedCard != null)
+            {
+                selectedCard.Background = Brushes.Transparent;
+                selectedCard.BorderBrush = borderBrush;
+                selectedCard = null;
+            }
+            customCard.BorderBrush = accentBrush;
+            customCard.Background = selectedBg;
+        };
+        customInputBox.TextChanged += (_, _) =>
+        {
+            if (customInputBox.Tag?.ToString() != "placeholder" && !string.IsNullOrWhiteSpace(customInputBox.Text))
+                selectedResponse = customInputBox.Text.Trim();
         };
-        outer.Children.Add(inputBox);
 
+        customCard.Child = customInputBox;
+        cardPanel.Children.Add(customCard);
+        outer.Children.Add(cardPanel);
+
+        // ── 하단 버튼 ──
         var buttonRow = new StackPanel
         {
             Orientation = Orientation.Horizontal,
-            HorizontalAlignment = HorizontalAlignment.Right,
-            Margin = new Thickness(0, 12, 0, 0),
+            HorizontalAlignment = HorizontalAlignment.Left,
+            Margin = new Thickness(0, 8, 0, 0),
         };
 
-        Border BuildActionButton(string label, Brush bg, Brush fg)
+        var skipBtn = new Border
         {
-            return new Border
-            {
-                Background = bg,
-                BorderBrush = bg,
-                BorderThickness = new Thickness(1),
-                CornerRadius = new CornerRadius(999),
-                Padding = new Thickness(12, 7, 12, 7),
-                Margin = new Thickness(8, 0, 0, 0),
-                Cursor = Cursors.Hand,
-                Child = new TextBlock
-                {
-                    Text = label,
-                    FontSize = 12,
-                    FontWeight = FontWeights.SemiBold,
-                    Foreground = fg,
-                },
-            };
-        }
-
-        var cancelBtn = BuildActionButton("취소", Brushes.Transparent, dangerBrush);
-        cancelBtn.BorderBrush = new SolidColorBrush(Color.FromArgb(0x40, 0xEF, 0x44, 0x44));
-        cancelBtn.MouseLeftButtonUp += (_, _) =>
+            Background = Brushes.Transparent,
+            BorderBrush = borderBrush,
+            BorderThickness = new Thickness(1),
+            CornerRadius = new CornerRadius(8),
+            Padding = new Thickness(16, 7, 16, 7),
+            Margin = new Thickness(0, 0, 8, 0),
+            Cursor = Cursors.Hand,
+            Child = new TextBlock { Text = "건너뛰기", FontSize = 12.5, Foreground = secondaryText },
+        };
+        skipBtn.MouseEnter += (_, _) => skipBtn.Background = hoverBg;
+        skipBtn.MouseLeave += (_, _) => skipBtn.Background = Brushes.Transparent;
+        skipBtn.MouseLeftButtonUp += (_, _) =>
         {
             RemoveUserAskCard();
             tcs.TrySetResult(null);
         };
-        buttonRow.Children.Add(cancelBtn);
+        buttonRow.Children.Add(skipBtn);
 
-        var submitBtn = BuildActionButton("전달", okBrush, Brushes.White);
+        var submitBtn = new Border
+        {
+            Background = accentBrush,
+            BorderThickness = new Thickness(0),
+            CornerRadius = new CornerRadius(8),
+            Padding = new Thickness(16, 7, 16, 7),
+            Cursor = Cursors.Hand,
+            Child = new TextBlock { Text = "제출", FontSize = 12.5, FontWeight = FontWeights.SemiBold, Foreground = Brushes.White },
+        };
         submitBtn.MouseLeftButtonUp += (_, _) =>
         {
-            var finalResponse = !string.IsNullOrWhiteSpace(inputBox.Text)
-                ? inputBox.Text.Trim()
+            var finalResponse = (customInputBox.Tag?.ToString() != "placeholder" && !string.IsNullOrWhiteSpace(customInputBox.Text))
+                ? customInputBox.Text.Trim()
                 : selectedResponse?.Trim();
 
             if (string.IsNullOrWhiteSpace(finalResponse))
                 finalResponse = defaultValue?.Trim();
-
             if (string.IsNullOrWhiteSpace(finalResponse))
                 return;
 
@@ -237,8 +288,8 @@ public partial class ChatWindow
             tcs.TrySetResult(finalResponse);
         };
         buttonRow.Children.Add(submitBtn);
-
         outer.Children.Add(buttonRow);
+
         container.Child = outer;
         _userAskCard = container;
 
@@ -246,7 +297,5 @@ public partial class ChatWindow
         container.BeginAnimation(UIElement.OpacityProperty, new DoubleAnimation(0, 1, TimeSpan.FromMilliseconds(180)));
         AddTranscriptElement(container);
         ForceScrollToEnd();
-        inputBox.Focus();
-        inputBox.CaretIndex = inputBox.Text.Length;
     }
 }

src/AxCopilot/Views/ChatWindow.VisualInteractionHelpers.cs

@@ -240,6 +240,30 @@ public partial class ChatWindow
             : null;
     }
 
+    /// <summary>VisualTree를 부모 방향으로 탐색하여 Tag가 설정된 T 타입 요소를 찾습니다.</summary>
+    private static T? FindAncestorWithTag<T>(DependencyObject? source) where T : FrameworkElement
+    {
+        while (source != null)
+        {
+            if (source is T fe && fe.Tag != null)
+                return fe;
+            source = VisualTreeHelper.GetParent(source);
+        }
+        return null;
+    }
+
+    /// <summary>VisualTree를 부모 방향으로 탐색하여 지정 T 타입 요소를 찾습니다.</summary>
+    private static T? FindAncestor<T>(DependencyObject? source) where T : DependencyObject
+    {
+        while (source != null)
+        {
+            if (source is T found)
+                return found;
+            source = VisualTreeHelper.GetParent(source);
+        }
+        return null;
+    }
+
     private static ControlTemplate BuildMinimalIconButtonTemplate()
     {
         var template = new ControlTemplate(typeof(Button));

src/AxCopilot/Views/ChatWindow.xaml

@@ -1053,19 +1053,37 @@
                                 </Button>
                             </WrapPanel>
                         </StackPanel>
-                        <!-- 우: 프리뷰 토글 버튼 -->
+                        <!-- 우: 미리보기 Split Button (Claude Desktop 스타일) -->
                         <StackPanel Grid.Column="2" Orientation="Horizontal" HorizontalAlignment="Right" VerticalAlignment="Center">
-                            <Button x:Name="BtnPreviewToggle" Style="{StaticResource GhostBtn}"
-                                    Click="BtnPreviewToggle_Click" ToolTip="미리보기 패널"
-                                    Padding="5,2.5" MinWidth="0">
+                            <Border CornerRadius="6" Background="Transparent">
                                 <StackPanel Orientation="Horizontal">
-                                    <Ellipse x:Name="PreviewDot" Width="5" Height="5" Fill="Gray"
-                                             Margin="0,0,4,0" VerticalAlignment="Center"/>
-                                    <TextBlock Text="프리뷰" FontSize="10.5"
-                                               Foreground="{DynamicResource PrimaryText}"
-                                               VerticalAlignment="Center"/>
+                                    <!-- 좌: 패널 토글 영역 -->
+                                    <Border x:Name="PreviewToggleArea" CornerRadius="6,0,0,6"
+                                            Background="Transparent" Padding="5,2.5,3,2.5"
+                                            Cursor="Hand" ToolTip="미리보기 패널 열기/닫기"
+                                            MouseLeftButtonUp="PreviewToggleArea_Click">
+                                        <StackPanel Orientation="Horizontal">
+                                            <TextBlock x:Name="PreviewIcon" Text="&#xE768;"
+                                                       FontFamily="Segoe MDL2 Assets" FontSize="10"
+                                                       Foreground="{DynamicResource SecondaryText}"
+                                                       VerticalAlignment="Center" Margin="0,0,4,0"/>
+                                            <TextBlock Text="미리보기" FontSize="10.5"
+                                                       Foreground="{DynamicResource PrimaryText}"
+                                                       VerticalAlignment="Center"/>
+                                        </StackPanel>
+                                    </Border>
+                                    <!-- 우: 셰브론 드롭다운 영역 -->
+                                    <Border x:Name="PreviewChevronArea" CornerRadius="0,6,6,0"
+                                            Background="Transparent" Padding="3,2.5,5,2.5"
+                                            Cursor="Hand" ToolTip="열린 미리보기 목록"
+                                            IsHitTestVisible="False" Opacity="0.35"
+                                            MouseLeftButtonUp="PreviewChevron_Click">
+                                        <TextBlock Text="&#xE70D;" FontFamily="Segoe MDL2 Assets" FontSize="8"
+                                                   Foreground="{DynamicResource SecondaryText}"
+                                                   VerticalAlignment="Center"/>
+                                    </Border>
                                 </StackPanel>
-                            </Button>
+                            </Border>
                         </StackPanel>
                     </Grid>
                 </Border>
@@ -1367,12 +1385,12 @@
                          ScrollViewer.VerticalScrollBarVisibility="Auto"
                          ScrollViewer.HorizontalScrollBarVisibility="Disabled"
                          ScrollViewer.CanContentScroll="True"
-                         ScrollViewer.IsDeferredScrollingEnabled="True"
+                         ScrollViewer.IsDeferredScrollingEnabled="False"
                          VirtualizingPanel.IsVirtualizing="True"
                          VirtualizingPanel.VirtualizationMode="Recycling"
                          VirtualizingPanel.ScrollUnit="Pixel"
-                         VirtualizingPanel.CacheLength="2"
-                         VirtualizingPanel.CacheLengthUnit="Item"
+                         VirtualizingPanel.CacheLength="3"
+                         VirtualizingPanel.CacheLengthUnit="Page"
                          UseLayoutRounding="True">
                     <ListBox.ItemsPanel>
                         <ItemsPanelTemplate>
@@ -1442,6 +1460,7 @@
 
                 <!-- 빈 상태 -->
                 <Grid x:Name="EmptyState" Grid.Row="3"
+                      Background="Transparent"
                       HorizontalAlignment="Stretch"
                       VerticalAlignment="Stretch"
                       MaxWidth="960"
@@ -2810,6 +2829,20 @@
                                                VerticalAlignment="Center"/>
                                 </StackPanel>
                             </Border>
+                            <!-- 계획 버튼 (실행 계획 존재 시 표시) -->
+                            <Border x:Name="BtnPlanViewer" Visibility="Collapsed"
+                                    CornerRadius="4" Padding="3.5,1" Margin="0,0,5,0"
+                                    Background="{DynamicResource HintBackground}"
+                                    BorderBrush="{DynamicResource BorderColor}" BorderThickness="1"
+                                    Cursor="Hand" ToolTip="실행 계획 보기"
+                                    MouseLeftButtonUp="BtnPlanViewer_Click">
+                                <StackPanel Orientation="Horizontal">
+                                    <TextBlock Text="&#xE8FD;" FontFamily="Segoe MDL2 Assets" FontSize="9"
+                                               Foreground="#10B981" VerticalAlignment="Center" Margin="0,0,3,0"/>
+                                    <TextBlock x:Name="PlanViewerLabel" Text="계획" FontSize="9" FontWeight="SemiBold"
+                                               Foreground="#10B981" VerticalAlignment="Center"/>
+                                </StackPanel>
+                            </Border>
                             <TextBlock x:Name="StatusElapsed" Text="" FontSize="8.25"
                                        Visibility="Collapsed"
                                        Foreground="{DynamicResource SecondaryText}"
@@ -3590,15 +3623,42 @@
                                                                FontSize="11"
                                                                Foreground="{DynamicResource SecondaryText}"/>
                                                 </StackPanel>
-                                                <TextBox x:Name="TxtOverlayPdfExportPath"
-                                                         Grid.Column="1"
-                                                         LostFocus="TxtOverlayPdfExportPath_LostFocus"
-                                                         Padding="9,7"
-                                                         Background="{DynamicResource LauncherBackground}"
-                                                         BorderBrush="{DynamicResource BorderColor}"
-                                                         BorderThickness="1"
-                                                 Foreground="{DynamicResource PrimaryText}"
-                                                         FontSize="12"/>
+                                                <Grid Grid.Column="1">
+                                                    <Grid.ColumnDefinitions>
+                                                        <ColumnDefinition Width="*"/>
+                                                        <ColumnDefinition Width="Auto"/>
+                                                    </Grid.ColumnDefinitions>
+                                                    <TextBox x:Name="TxtOverlayPdfExportPath"
+                                                             LostFocus="TxtOverlayPdfExportPath_LostFocus"
+                                                             Padding="9,7"
+                                                             IsReadOnly="True"
+                                                             Background="{DynamicResource LauncherBackground}"
+                                                             BorderBrush="{DynamicResource BorderColor}"
+                                                             BorderThickness="1"
+                                                             Foreground="{DynamicResource PrimaryText}"
+                                                             FontSize="12"/>
+                                                    <Border x:Name="BtnBrowsePdfExportPath"
+                                                            Grid.Column="1"
+                                                            Cursor="Hand"
+                                                            Background="{DynamicResource ItemHoverBackground}"
+                                                            BorderBrush="{DynamicResource BorderColor}"
+                                                            BorderThickness="1"
+                                                            CornerRadius="6"
+                                                            Padding="8,6"
+                                                            Margin="6,0,0,0"
+                                                            VerticalAlignment="Center"
+                                                            ToolTip="폴더 선택"
+                                                            MouseLeftButtonUp="BtnBrowsePdfExportPath_Click"
+                                                            MouseEnter="OverlayActionBtn_MouseEnter"
+                                                            MouseLeave="OverlayActionBtn_MouseLeave"
+                                                            MouseLeftButtonDown="OverlayActionBtn_MouseLeftButtonDown">
+                                                        <TextBlock Text="&#xED25;"
+                                                                   FontFamily="Segoe MDL2 Assets"
+                                                                   FontSize="13"
+                                                                   Foreground="{DynamicResource AccentColor}"
+                                                                   VerticalAlignment="Center"/>
+                                                    </Border>
+                                                </Grid>
                                             </Grid>
                                             <Border Background="{DynamicResource ItemBackground}"
                                                     BorderBrush="{DynamicResource BorderColor}"
@@ -4497,7 +4557,8 @@
                                                                    TextWrapping="Wrap"
                                                                    Foreground="{DynamicResource SecondaryText}"/>
                                                     </StackPanel>
-                                                    <Border Grid.Column="1"
+                                                    <Border x:Name="BtnOverlayOpenAuditLog"
+                                                            Grid.Column="1"
                                                             Cursor="Hand"
                                                             Background="{DynamicResource ItemHoverBackground}"
                                                             BorderBrush="{DynamicResource BorderColor}"
@@ -4505,7 +4566,10 @@
                                                             CornerRadius="8"
                                                             Padding="10,6"
                                                             Margin="12,0,0,0"
-                                                            MouseLeftButtonUp="OverlayOpenAuditLogBtn_MouseLeftButtonUp">
+                                                            MouseLeftButtonUp="OverlayOpenAuditLogBtn_MouseLeftButtonUp"
+                                                            MouseEnter="OverlayActionBtn_MouseEnter"
+                                                            MouseLeave="OverlayActionBtn_MouseLeave"
+                                                            MouseLeftButtonDown="OverlayActionBtn_MouseLeftButtonDown">
                                                         <TextBlock Text="폴더 열기"
                                                                    FontSize="12"
                                                                    FontWeight="SemiBold"

src/AxCopilot/Views/ChatWindow.xaml.cs

@@ -251,7 +251,7 @@ public partial class ChatWindow : Window
             _gitRefreshTimer.Stop();
             await RefreshGitBranchStatusAsync();
         };
-        _conversationSearchTimer = new DispatcherTimer { Interval = TimeSpan.FromMilliseconds(140) };
+        _conversationSearchTimer = new DispatcherTimer { Interval = TimeSpan.FromMilliseconds(300) };
         _conversationSearchTimer.Tick += (_, _) =>
         {
             _conversationSearchTimer.Stop();
@@ -301,15 +301,15 @@ public partial class ChatWindow : Window
             _conversationPersistTimer.Stop();
             FlushPendingConversationPersists();
         };
-        _agentUiEventTimer = new DispatcherTimer { Interval = TimeSpan.FromMilliseconds(140) };
+        _agentUiEventTimer = new DispatcherTimer { Interval = TimeSpan.FromMilliseconds(200) };
         _agentUiEventTimer.Tick += (_, _) =>
         {
             _agentUiEventTimer.Stop();
             _agentUiEventTimer.Interval = _isStreaming
                 ? (IsLightweightLiveProgressMode()
-                    ? TimeSpan.FromMilliseconds(420)
-                    : TimeSpan.FromMilliseconds(300))
-                : TimeSpan.FromMilliseconds(140);
+                    ? TimeSpan.FromMilliseconds(500)
+                    : TimeSpan.FromMilliseconds(350))
+                : TimeSpan.FromMilliseconds(200);
             FlushPendingAgentUiEvent();
         };
         _agentProgressHintTimer = new DispatcherTimer { Interval = TimeSpan.FromSeconds(1) };
@@ -320,7 +320,7 @@ public partial class ChatWindow : Window
             _tokenUsagePopupCloseTimer.Stop();
             CloseTokenUsagePopupIfIdle();
         };
-        _responsiveLayoutTimer = new DispatcherTimer { Interval = TimeSpan.FromMilliseconds(120) };
+        _responsiveLayoutTimer = new DispatcherTimer { Interval = TimeSpan.FromMilliseconds(250) };
         _responsiveLayoutTimer.Tick += (_, _) =>
         {
             _responsiveLayoutTimer.Stop();
@@ -379,11 +379,17 @@ public partial class ChatWindow : Window
             UpdateInputBoxHeight();
             InputBox.Focus();
             // ── 무거운 작업은 유휴 시점에 비동기 실행 ──
+            // A-1: 패널 이벤트 위임 1회 초기화 — 개별 람다 대신 부모 레벨에서 처리
+            InitConversationPanelDelegation();
+            InitTopicPanelDelegation();
+            InitPreviewSplitButtonHover();
+            InitPlanButtonHover();
+
             Dispatcher.BeginInvoke(() =>
             {
                 TemplateService.LoadCustomMoods(_settings.Settings.Llm.CustomMoods);
-                BuildTopicButtons();
                 RestoreLastConversations();
+                BuildTopicButtons();
                 RefreshConversationList();
                 UpdateResponsiveChatLayout();
                 UpdateTaskSummaryIndicators();
@@ -471,13 +477,27 @@ public partial class ChatWindow : Window
             _settings.SettingsChanged -= Settings_SettingsChanged;
             SubAgentTool.StatusChanged -= OnSubAgentStatusChanged;
             foreach (var cts in _tabStreamCts.Values) cts.Cancel();
+
+            // 모든 DispatcherTimer 명시적 Stop — auto-stop에만 의존하지 않음
             _cursorTimer.Stop();
             _elapsedTimer.Stop();
             _typingTimer.Stop();
             _conversationSearchTimer.Stop();
             _inputUiRefreshTimer.Stop();
             _responsiveLayoutTimer.Stop();
+            _gitRefreshTimer.Stop();
+            _executionHistoryRenderTimer.Stop();
+            _taskSummaryRefreshTimer.Stop();
+            _conversationPersistTimer.Stop();
+            _agentUiEventTimer.Stop();
+            _agentProgressHintTimer.Stop();
+            _tokenUsagePopupCloseTimer.Stop();
+            _smoothScrollTimer?.Stop();
+            _sidebarAnimTimer?.Stop();
+            _fileBrowserRefreshTimer?.Stop();
+
             StopRainbowGlow();
+            StopAgentEventProcessor();
             _llm.Dispose();
         };
     }
@@ -688,25 +708,18 @@ public partial class ChatWindow : Window
         animation.Completed += (_, _) => ScrollTranscriptToVerticalOffset(targetOffset);
 
         // ScrollViewer에 직접 애니메이션을 적용할 수 없으므로 타이머 기반으로 보간
+        // 기존 스크롤 애니메이션이 진행 중이면 즉시 종료
+        _smoothScrollTimer?.Stop();
         var startTime = DateTime.UtcNow;
-        var timer = new DispatcherTimer { Interval = TimeSpan.FromMilliseconds(16) }; // ~60fps
-        EventHandler tickHandler = null!;
-        tickHandler = (_, _) =>
+        _smoothScrollStartOffset = currentOffset;
+        _smoothScrollDiff = diff;
+        _smoothScrollStartTime = startTime;
+        if (_smoothScrollTimer == null)
         {
-            var elapsed = (DateTime.UtcNow - startTime).TotalMilliseconds;
-            var progress = Math.Min(elapsed / 200.0, 1.0);
-            var eased = 1.0 - Math.Pow(1.0 - progress, 3);
-            var offset = currentOffset + diff * eased;
-            ScrollTranscriptToVerticalOffset(offset);
-
-            if (progress >= 1.0)
-            {
-                timer.Stop();
-                timer.Tick -= tickHandler;
-            }
-        };
-        timer.Tick += tickHandler;
-        timer.Start();
+            _smoothScrollTimer = new DispatcherTimer { Interval = TimeSpan.FromMilliseconds(32) }; // ~30fps (충분히 부드러움)
+            _smoothScrollTimer.Tick += SmoothScrollTimer_Tick;
+        }
+        _smoothScrollTimer.Start();
     }
 
     // ─── 대화 제목 인라인 편집 ──────────────────────────────────────────
@@ -1311,6 +1324,16 @@ public partial class ChatWindow : Window
             ? Visibility.Visible
             : Visibility.Collapsed;
         if (!isOwningTab) PauseIcon.Text = "\uE769";
+
+        // 스트리밍 중인 탭이 아니면 펄스 닷·상태 바 숨김 (다른 탭 작업 상태가 보이지 않도록)
+        // 스트리밍 탭으로 복귀 시 자동 복원
+        if (PulseDotBar != null)
+        {
+            if (!isOwningTab)
+                PulseDotBar.Visibility = Visibility.Collapsed;
+            else if (_streamingTabs.Count > 0)
+                PulseDotBar.Visibility = Visibility.Visible;
+        }
     }
 
     private void TabChat_Checked(object sender, RoutedEventArgs e)
@@ -2223,24 +2246,18 @@ public partial class ChatWindow : Window
     {
         var duration = 200.0;
         var start = DateTime.UtcNow;
-        var timer = new DispatcherTimer { Interval = TimeSpan.FromMilliseconds(10) };
-        EventHandler tickHandler = null!;
-        tickHandler = (_, _) =>
+        _sidebarAnimTimer?.Stop();
+        _sidebarAnimFrom = from;
+        _sidebarAnimTo = to;
+        _sidebarAnimStart = start;
+        _sidebarAnimDuration = duration;
+        _sidebarAnimComplete = onComplete;
+        if (_sidebarAnimTimer == null)
         {
-            var elapsed = (DateTime.UtcNow - start).TotalMilliseconds;
-            var t = Math.Min(elapsed / duration, 1.0);
-            t = 1 - (1 - t) * (1 - t);
-            SidebarColumn.Width = new GridLength(from + (to - from) * t);
-            if (elapsed >= duration)
-            {
-                timer.Stop();
-                timer.Tick -= tickHandler;
-                SidebarColumn.Width = new GridLength(to);
-                onComplete?.Invoke();
-            }
-        };
-        timer.Tick += tickHandler;
-        timer.Start();
+            _sidebarAnimTimer = new DispatcherTimer { Interval = TimeSpan.FromMilliseconds(32) };
+            _sidebarAnimTimer.Tick += SidebarAnimTimer_Tick;
+        }
+        _sidebarAnimTimer.Start();
     }
 
     // ─── 대화 목록 ────────────────────────────────────────────────────────
@@ -2254,6 +2271,27 @@ public partial class ChatWindow : Window
         _conversationSearchTimer.Start();
     }
 
+    // ─── 사이드바 애니메이션 (재사용 타이머) ──────────────────────────────
+
+    private DispatcherTimer? _sidebarAnimTimer;
+    private double _sidebarAnimFrom, _sidebarAnimTo, _sidebarAnimDuration;
+    private DateTime _sidebarAnimStart;
+    private Action? _sidebarAnimComplete;
+
+    private void SidebarAnimTimer_Tick(object? sender, EventArgs e)
+    {
+        var elapsed = (DateTime.UtcNow - _sidebarAnimStart).TotalMilliseconds;
+        var t = Math.Min(elapsed / _sidebarAnimDuration, 1.0);
+        t = 1 - (1 - t) * (1 - t);
+        SidebarColumn.Width = new GridLength(_sidebarAnimFrom + (_sidebarAnimTo - _sidebarAnimFrom) * t);
+        if (elapsed >= _sidebarAnimDuration)
+        {
+            _sidebarAnimTimer?.Stop();
+            SidebarColumn.Width = new GridLength(_sidebarAnimTo);
+            _sidebarAnimComplete?.Invoke();
+        }
+    }
+
     private static string FormatDate(DateTime dt)
     {
         var diff = DateTime.Now - dt;
@@ -5805,6 +5843,12 @@ public partial class ChatWindow : Window
             {
                 await ShowTypedAssistantPreviewAsync(assistantContent, streamToken);
             }
+            else
+            {
+                // 에이전트 루프 완료 시 assistantContent가 비어 있으면
+                // ShowTypedAssistantPreviewAsync가 호출되지 않아 라이브 카드가 남음 → 명시적 제거
+                RemoveAgentLiveCard();
+            }
         }
         catch (OperationCanceledException)
         {
@@ -6034,9 +6078,6 @@ public partial class ChatWindow : Window
                     PreviewWindow.RefreshIfOpen(evt.FilePath);
                 else
                     TryShowPreview(evt.FilePath);
-
-                if (!PreviewWindow.IsOpen)
-                    TryShowPreview(evt.FilePath);
             }
         }
     }
@@ -6197,11 +6238,15 @@ public partial class ChatWindow : Window
         {
             case "active":
                 sb.AppendLine("IMPORTANT: Folder Data Usage = ACTIVE. You have 'document_read' and 'folder_map' tools available.");
-                sb.AppendLine("Before creating reports, use folder_map to scan the work folder structure. " +
-                    "Then EVALUATE whether each document is RELEVANT to the user's current request topic. " +
-                    "Only use document_read on files that are clearly related to the conversation subject. " +
-                    "Do NOT read or reference files that are unrelated to the user's request, even if they exist in the folder. " +
-                    "In your planning step, list which files you plan to read and explain WHY they are relevant.");
+                sb.AppendLine("Use selective exploration. Start with glob or grep when the request already has a clear topic.");
+                sb.AppendLine("Use folder_map only when the workspace structure is unclear or the request is repo-wide/open-ended.");
+                sb.AppendLine("[CRITICAL] FILE SELECTION STRATEGY — DO NOT READ ALL FILES:");
+                sb.AppendLine("  1. Identify candidate files by filename or topic keywords first.");
+                sb.AppendLine("  2. Read ONLY files that clearly match the user's topic. Skip unrelated topics.");
+                sb.AppendLine("  3. Maximum 2-3 relevant files for the first pass. Expand only when evidence shows more files are needed.");
+                sb.AppendLine("  4. Do NOT read every file 'just in case'. Broad reading without evidence is forbidden.");
+                sb.AppendLine("  5. If no files match the topic, proceed WITHOUT reading any workspace files.");
+                sb.AppendLine("VIOLATION: Reading all files in the folder is FORBIDDEN. It wastes tokens and degrades quality.");
                 break;
             case "passive":
                 sb.AppendLine("Folder Data Usage = PASSIVE. You have 'document_read' and 'folder_map' tools. " +
@@ -6297,11 +6342,14 @@ public partial class ChatWindow : Window
         sb.AppendLine("IMPORTANT: When creating documents with dates, always use today's actual date above.");
 
         sb.AppendLine("\n## Core Workflow (MANDATORY — follow this order)");
-        sb.AppendLine("1. ORIENT: Run folder_map (depth=2) to understand project structure. Check .gitignore, README, config files.");
+        sb.AppendLine("1. ORIENT: Choose the smallest exploration that matches the request.");
+        sb.AppendLine("   - If the request is file-specific, bug-specific, symbol-specific, or topic-specific: start with grep/glob and targeted file_read.");
+        sb.AppendLine("   - Only run folder_map (depth=2) when the repository structure is genuinely unclear or the request is repo-wide/open-ended.");
         sb.AppendLine("2. BASELINE: If tests exist, run build_run action='test' FIRST to establish baseline. Record pass/fail count.");
-        sb.AppendLine("3. ANALYZE: Use grep (with context_lines=2) + file_read to deeply understand the code you'll modify.");
+        sb.AppendLine("3. ANALYZE: Use grep (with context_lines=2) + targeted file_read to deeply understand the code you'll modify.");
         sb.AppendLine("   - Always check callers/references: grep for function/class names to find all usage points.");
         sb.AppendLine("   - Read test files related to the code you're changing to understand expected behavior.");
+        sb.AppendLine("   - Keep the first reading pass narrow (usually 1-5 files) unless evidence shows the scope is larger.");
         sb.AppendLine("4. PLAN: Build an internal execution outline and impact assessment before editing.");
         sb.AppendLine("   - Present the outline explicitly only when the user asks for a plan or the change is clearly high risk.");
         sb.AppendLine("   - Explain WHY each change is needed and what could break.");
@@ -6378,8 +6426,10 @@ public partial class ChatWindow : Window
         sb.Append(BuildSubAgentDelegationSection(true));
 
         // 폴더 데이터 활용
-        sb.AppendLine("\nFolder Data Usage = ACTIVE. Use folder_map and file_read to understand the codebase.");
-        sb.AppendLine("Analyze project structure before making changes. Read relevant files to understand context.");
+        sb.AppendLine("\nFolder Data Usage = ACTIVE.");
+        sb.AppendLine("Prefer grep/glob + targeted file_read for narrow requests.");
+        sb.AppendLine("Use folder_map only when structure is unclear or the request is repo-wide.");
+        sb.AppendLine("Read only files that are relevant to the current question. Avoid broad codebase sweeps without evidence.");
 
         // 프리셋 시스템 프롬프트
         lock (_convLock)
@@ -8846,6 +8896,15 @@ public partial class ChatWindow : Window
         else
             foreach (var cts in _tabStreamCts.Values) cts.Cancel();
 
+        // 대기열 정리: 실행 중 + 대기 중 항목 모두 제거 (중지는 "전부 멈춤"을 의미)
+        lock (_convLock)
+        {
+            _draftQueueProcessor.CancelRunning(ChatSession, _activeTab, _storage);
+            _draftQueueProcessor.ClearQueued(ChatSession, _activeTab, _storage);
+            _runningDraftId = null;
+        }
+        RefreshDraftQueueUi();
+
         // 즉시 UI 상태 정리 — 에이전트 루프의 finally가 비동기로 도달할 때까지 대기하지 않음
         StopLiveAgentProgressHints();
         RemoveAgentLiveCard();
@@ -9491,6 +9550,24 @@ public partial class ChatWindow : Window
         return "";
     }
 
+    // ─── 부드러운 스크롤 애니메이션 (재사용 타이머) ──────────────────────
+
+    private DispatcherTimer? _smoothScrollTimer;
+    private double _smoothScrollStartOffset;
+    private double _smoothScrollDiff;
+    private DateTime _smoothScrollStartTime;
+
+    private void SmoothScrollTimer_Tick(object? sender, EventArgs e)
+    {
+        var elapsed = (DateTime.UtcNow - _smoothScrollStartTime).TotalMilliseconds;
+        var progress = Math.Min(elapsed / 200.0, 1.0);
+        var eased = 1.0 - Math.Pow(1.0 - progress, 3);
+        ScrollTranscriptToVerticalOffset(_smoothScrollStartOffset + _smoothScrollDiff * eased);
+
+        if (progress >= 1.0)
+            _smoothScrollTimer?.Stop();
+    }
+
     // ─── 무지개 글로우 애니메이션 ─────────────────────────────────────────
 
     private DispatcherTimer? _rainbowTimer;
@@ -11897,9 +11974,75 @@ public partial class ChatWindow : Window
 
     private void OverlayOpenAuditLogBtn_MouseLeftButtonUp(object sender, MouseButtonEventArgs e)
     {
+        // 클릭 효과 리셋
+        if (sender is Border border)
+        {
+            border.Opacity = 1.0;
+            border.RenderTransform = null;
+        }
         try { System.Diagnostics.Process.Start("explorer.exe", Services.AuditLogService.GetAuditFolder()); } catch { }
     }
 
+    private void BtnBrowsePdfExportPath_Click(object sender, MouseButtonEventArgs e)
+    {
+        // 클릭 효과 리셋
+        if (sender is Border border)
+        {
+            border.Opacity = 1.0;
+            border.RenderTransform = null;
+        }
+
+        var dlg = new System.Windows.Forms.FolderBrowserDialog
+        {
+            Description = "PDF 내보내기 기본 폴더를 선택하세요",
+            ShowNewFolderButton = true,
+            UseDescriptionForTitle = true,
+        };
+
+        var current = _settings.Settings.Llm.PdfExportPath;
+        if (!string.IsNullOrWhiteSpace(current) && Directory.Exists(current))
+            dlg.SelectedPath = current;
+
+        if (dlg.ShowDialog() != System.Windows.Forms.DialogResult.OK)
+            return;
+
+        _settings.Settings.Llm.PdfExportPath = dlg.SelectedPath;
+        if (TxtOverlayPdfExportPath != null)
+            TxtOverlayPdfExportPath.Text = dlg.SelectedPath;
+        PersistOverlaySettingsState(refreshOverlayDeferredInputs: false);
+    }
+
+    /// <summary>설정 오버레이 액션 버튼 공통 호버/클릭 효과.</summary>
+    private void OverlayActionBtn_MouseEnter(object sender, MouseEventArgs e)
+    {
+        if (sender is Border border)
+        {
+            border.Opacity = 0.85;
+            border.Background = TryFindResource("ItemActiveBackground") as Brush
+                                ?? TryFindResource("ItemHoverBackground") as Brush
+                                ?? border.Background;
+        }
+    }
+
+    private void OverlayActionBtn_MouseLeave(object sender, MouseEventArgs e)
+    {
+        if (sender is Border border)
+        {
+            border.Opacity = 1.0;
+            border.Background = TryFindResource("ItemHoverBackground") as Brush ?? border.Background;
+        }
+    }
+
+    private void OverlayActionBtn_MouseLeftButtonDown(object sender, MouseButtonEventArgs e)
+    {
+        if (sender is Border border)
+        {
+            border.Opacity = 0.65;
+            border.RenderTransform = new ScaleTransform(0.96, 0.96);
+            border.RenderTransformOrigin = new Point(0.5, 0.5);
+        }
+    }
+
     private void ChkOverlayEnableDragDropAiActions_Changed(object sender, RoutedEventArgs e)
     {
         if (_isOverlaySettingsSyncing || ChkOverlayEnableDragDropAiActions == null)
@@ -14222,15 +14365,21 @@ public partial class ChatWindow : Window
 
     private void BtnDeleteAll_Click(object sender, RoutedEventArgs e)
     {
+        var tabLabel = _activeTab switch
+        {
+            "Cowork" => "코워크",
+            "Code" => "코드",
+            _ => "채팅"
+        };
         var result = CustomMessageBox.Show(
-            "저장된 모든 대화 내역을 삭제하시겠습니까?\n이 작업은 되돌릴 수 없습니다.",
-            "대화 전체 삭제",
+            $"'{tabLabel}' 탭의 모든 대화 내역을 삭제하시겠습니까?\n이 작업은 되돌릴 수 없습니다.",
+            $"{tabLabel} 대화 전체 삭제",
             MessageBoxButton.YesNo,
             MessageBoxImage.Warning);
 
         if (result != MessageBoxResult.Yes) return;
 
-        _storage.DeleteAll();
+        _storage.DeleteAllByTab(_activeTab);
         lock (_convLock)
         {
             ChatSession?.ClearCurrentConversation(_activeTab);
@@ -14377,13 +14526,20 @@ public partial class ChatWindow : Window
             return;
         }
 
-        await RefreshGitBranchStatusAsync();
-        _gitBranchSearchText = "";
-        if (GitBranchSearchBox != null)
-            GitBranchSearchBox.Text = "";
-        BuildGitBranchPopup();
-        GitBranchPopup.IsOpen = true;
-        GitBranchSearchBox?.Focus();
+        try
+        {
+            await RefreshGitBranchStatusAsync();
+            _gitBranchSearchText = "";
+            if (GitBranchSearchBox != null)
+                GitBranchSearchBox.Text = "";
+            BuildGitBranchPopup();
+            GitBranchPopup.IsOpen = true;
+            GitBranchSearchBox?.Focus();
+        }
+        catch (Exception ex)
+        {
+            Services.LogService.Error($"Git branch refresh failed: {ex.Message}");
+        }
     }
 
     private void GitBranchSearchBox_TextChanged(object sender, TextChangedEventArgs e)
@@ -14463,9 +14619,17 @@ public partial class ChatWindow : Window
         return value.ToString("N0");
     }
 
-    private static void UpdateCircularUsageArc(System.Windows.Shapes.Path path, double ratio, double centerX, double centerY, double radius)
+    private double _lastArcRatio = -1;
+
+    private void UpdateCircularUsageArc(System.Windows.Shapes.Path path, double ratio, double centerX, double centerY, double radius)
     {
         ratio = Math.Clamp(ratio, 0, 0.9999);
+
+        // 비율 변화가 1% 미만이면 렌더링 생략 (250ms마다 호출되므로 불필요한 재생성 방지)
+        if (Math.Abs(ratio - _lastArcRatio) < 0.01)
+            return;
+        _lastArcRatio = ratio;
+
         if (ratio <= 0)
         {
             path.Data = Geometry.Empty;

src/AxCopilot/Views/LauncherWindow.xaml.cs

@@ -38,6 +38,12 @@ public partial class LauncherWindow : Window
     private System.Windows.Threading.DispatcherTimer? _indexStatusTimer;
     private System.Windows.Threading.DispatcherTimer? _toastTimer;
 
+    // 이벤트 해제를 위해 핸들러 참조 보관
+    private EventHandler? _closeRequestedHandler;
+    private EventHandler<string>? _notificationRequestedHandler;
+    private System.ComponentModel.PropertyChangedEventHandler? _vmPropertyChangedHandler;
+    private EventHandler? _indexRebuiltHandler;
+
     /// <summary>Ctrl+, 단축키로 설정 창을 여는 콜백 (App.xaml.cs에서 주입)</summary>
     public Action? OpenSettingsAction { get; set; }
 
@@ -52,36 +58,38 @@ public partial class LauncherWindow : Window
         InitializeComponent();
         DataContext = vm;
 
-        vm.CloseRequested += (_, _) => Hide();
-        vm.NotificationRequested += (_, msg) => ShowNotification(msg);
-
-        // InputText가 코드에서 변경될 때 커서를 끝으로 이동
-        // (F1→"help", Ctrl+B→"fav", Ctrl+D→"cd Downloads" 등 자동 입력 후 위화감 해소)
-        vm.PropertyChanged += (_, e) =>
+        _closeRequestedHandler = (_, _) => Hide();
+        _notificationRequestedHandler = (_, msg) => ShowNotification(msg);
+        _vmPropertyChangedHandler = (_, e) =>
         {
             if (e.PropertyName == nameof(LauncherViewModel.InputText))
             {
-                // DispatcherPriority.Input: 바인딩 업데이트가 완료된 직후 실행
                 Dispatcher.InvokeAsync(
                     () => { if (InputBox != null) InputBox.CaretIndex = InputBox.Text.Length; },
                     System.Windows.Threading.DispatcherPriority.Input);
             }
         };
 
+        vm.CloseRequested += _closeRequestedHandler;
+        vm.NotificationRequested += _notificationRequestedHandler;
+        vm.PropertyChanged += _vmPropertyChangedHandler;
+
         // 인덱싱 완료 시 상태 표시
         var app = (App)System.Windows.Application.Current;
         if (app.IndexService != null)
         {
-            app.IndexService.IndexRebuilt += (_, _) =>
+            _indexRebuiltHandler = (_, _) =>
             {
                 Dispatcher.BeginInvoke(() =>
                 {
-                    var svc = app.IndexService;
+                    var svc = ((App)System.Windows.Application.Current).IndexService;
+                    if (svc == null) return;
                     ShowIndexStatus(
                         $"✓ {svc.LastIndexCount:N0}개 항목 색인됨 ({svc.LastIndexDuration.TotalSeconds:F1}초)",
                         TimeSpan.FromSeconds(5));
                 });
             };
+            app.IndexService.IndexRebuilt += _indexRebuiltHandler;
         }
 
         if (CurrentApp?.SettingsService != null)
@@ -103,6 +111,7 @@ public partial class LauncherWindow : Window
 
     private static readonly Random _iconRng = new();
     private System.Windows.Media.Animation.Storyboard? _iconStoryboard;
+    private System.Windows.Threading.DispatcherTimer? _iconAnimationDelayTimer;
     private System.Windows.Threading.DispatcherTimer? _rainbowTimer;
 
     /// <summary>외부에서 입력 텍스트를 설정합니다 (AI 명령 전달용).</summary>
@@ -225,6 +234,8 @@ public partial class LauncherWindow : Window
     /// <summary>아이콘 애니메이션을 중지하고 모든 픽셀을 완전 점등 상태로 복원합니다.</summary>
     private void ResetIconAnimation()
     {
+        _iconAnimationDelayTimer?.Stop();
+        _iconAnimationDelayTimer = null;
         _iconStoryboard?.Stop();
         _iconStoryboard = null;
         var pixels = new[] { PixelBlue, PixelGreen1, PixelRed, PixelGreen2 };
@@ -583,8 +594,23 @@ public partial class LauncherWindow : Window
         _iconStoryboard = sb;
         sb.Completed += (_, _) =>
         {
-            if (_vm.EnableIconAnimation && IsVisible)
-                ApplyRandomIconAnimation();
+            if (!_vm.EnableIconAnimation || !IsVisible) return;
+            // P3: 즉시 재귀 대신 8초 딜레이 — Storyboard+애니메이션 객체 할당 빈도 75% 감소
+            _iconAnimationDelayTimer?.Stop();
+            if (_iconAnimationDelayTimer == null)
+            {
+                _iconAnimationDelayTimer = new System.Windows.Threading.DispatcherTimer
+                {
+                    Interval = TimeSpan.FromSeconds(8)
+                };
+                _iconAnimationDelayTimer.Tick += (__, ___) =>
+                {
+                    _iconAnimationDelayTimer?.Stop();
+                    if (_vm.EnableIconAnimation && IsVisible)
+                        ApplyRandomIconAnimation();
+                };
+            }
+            _iconAnimationDelayTimer.Start();
         };
         sb.Begin(this, true);
     }
@@ -626,6 +652,7 @@ public partial class LauncherWindow : Window
     private void DiamondIcon_Click(object sender, MouseButtonEventArgs e)
     {
         if (!_vm.EnableIconAnimation) return;
+        _iconAnimationDelayTimer?.Stop(); // 딜레이 대기 중이면 취소 후 즉시 전환
         ApplyRandomIconAnimation();
     }
 
@@ -1482,28 +1509,30 @@ public partial class LauncherWindow : Window
         var fadeIn = (System.Windows.Media.Animation.Storyboard)FindResource("ToastFadeIn");
         fadeIn.Begin(this);
 
-        _toastTimer?.Stop();
-        _toastTimer = new System.Windows.Threading.DispatcherTimer
+        // 타이머 재사용 — 매번 new 할당 방지
+        if (_toastTimer == null)
         {
-            Interval = TimeSpan.FromSeconds(2)
-        };
-        _toastTimer.Tick += (_, _) =>
-        {
-            _toastTimer.Stop();
-            // 페이드아웃 후 Collapsed
-            var fadeOut = (System.Windows.Media.Animation.Storyboard)FindResource("ToastFadeOut");
-            EventHandler? onCompleted = null;
-            onCompleted = (__, ___) =>
-            {
-                fadeOut.Completed -= onCompleted;
-                ToastOverlay.Visibility = Visibility.Collapsed;
-            };
-            fadeOut.Completed += onCompleted;
-            fadeOut.Begin(this);
-        };
+            _toastTimer = new System.Windows.Threading.DispatcherTimer { Interval = TimeSpan.FromSeconds(2) };
+            _toastTimer.Tick += ToastTimer_Tick;
+        }
+        _toastTimer.Stop();
         _toastTimer.Start();
     }
 
+    private void ToastTimer_Tick(object? sender, EventArgs e)
+    {
+        _toastTimer?.Stop();
+        var fadeOut = (System.Windows.Media.Animation.Storyboard)FindResource("ToastFadeOut");
+        EventHandler? onCompleted = null;
+        onCompleted = (__, ___) =>
+        {
+            fadeOut.Completed -= onCompleted;
+            ToastOverlay.Visibility = Visibility.Collapsed;
+        };
+        fadeOut.Completed += onCompleted;
+        fadeOut.Begin(this);
+    }
+
     private void ShowIndexStatus(string message, TimeSpan duration)
     {
         IndexStatusText.Text = message;
@@ -1983,10 +2012,24 @@ public partial class LauncherWindow : Window
 
     protected override void OnClosed(EventArgs e)
     {
+        // 이벤트 구독 해제 — ViewModel/서비스가 Window보다 오래 살면 GC 누수 방지
+        if (_closeRequestedHandler != null) _vm.CloseRequested -= _closeRequestedHandler;
+        if (_notificationRequestedHandler != null) _vm.NotificationRequested -= _notificationRequestedHandler;
+        if (_vmPropertyChangedHandler != null) _vm.PropertyChanged -= _vmPropertyChangedHandler;
+        if (_indexRebuiltHandler != null)
+        {
+            var app = System.Windows.Application.Current as App;
+            if (app?.IndexService != null)
+                app.IndexService.IndexRebuilt -= _indexRebuiltHandler;
+        }
         if (CurrentApp?.SettingsService != null)
             CurrentApp.SettingsService.SettingsChanged -= OnSettingsChanged;
 
         StopRainbowGlow();
+        _toastTimer?.Stop();
+        _indexStatusTimer?.Stop();
+        _iconAnimationDelayTimer?.Stop();
+        _iconAnimationDelayTimer = null;
         _iconStoryboard?.Stop();
         _iconStoryboard = null;
 
@@ -2014,6 +2057,7 @@ public partial class LauncherWindow : Window
         _quickLookWindow = null;
         StopWidgetUpdates();
         StopRainbowGlow();       // 숨김 상태에서 CPU 낭비 방지
+        _iconAnimationDelayTimer?.Stop(); // 딜레이 대기도 중지
         _iconStoryboard?.Stop(); // 숨김 상태에서 애니메이션 중지
         _iconStoryboard = null;
         SaveRememberedPosition();

src/AxCopilot/Views/PreviewWindow.xaml.cs

@@ -31,6 +31,7 @@ public partial class PreviewWindow : Window
     private static readonly HashSet<string> PreviewableExtensions = new(StringComparer.OrdinalIgnoreCase)
     {
         ".html", ".htm", ".md", ".csv", ".txt", ".json", ".xml", ".log",
+        ".docx", ".xlsx", ".pptx",
     };
 
     public PreviewWindow()
@@ -358,6 +359,24 @@ public partial class PreviewWindow : Window
                     PreviewBrowser.Visibility = Visibility.Visible;
                     break;
 
+                case ".docx":
+                    if (!_webViewInitialized) return;
+                    PreviewBrowser.NavigateToString(Services.Agent.DocxToHtmlConverter.Convert(filePath));
+                    PreviewBrowser.Visibility = Visibility.Visible;
+                    break;
+
+                case ".xlsx":
+                    if (!_webViewInitialized) return;
+                    PreviewBrowser.NavigateToString(Services.Agent.XlsxToHtmlConverter.Convert(filePath));
+                    PreviewBrowser.Visibility = Visibility.Visible;
+                    break;
+
+                case ".pptx":
+                    if (!_webViewInitialized) return;
+                    PreviewBrowser.NavigateToString(Services.Agent.PptxToHtmlConverter.Convert(filePath));
+                    PreviewBrowser.Visibility = Visibility.Visible;
+                    break;
+
                 case ".txt":
                 case ".json":
                 case ".xml":

src/AxCopilot/Views/WorkflowAnalyzerWindow.xaml.cs

@@ -81,7 +81,7 @@ public partial class WorkflowAnalyzerWindow : Window
     {
         if (!Dispatcher.CheckAccess())
         {
-            Dispatcher.Invoke(() => OnAgentEvent(evt));
+            _ = Dispatcher.InvokeAsync(() => OnAgentEvent(evt));
             return;
         }