코드탭 통계 대시보드 병합 및 빈화면 동기화 보강

외부 작업 로그 기준으로 코드탭 병합 누락분을 검토하고 기존 컨텍스트 영속화 경로는 유지한 채 Code 사용량 대시보드만 선택적으로 병합했습니다.

CodeStatsSummary, CodeStatsAggregator, ChatWindow.CodeStatsPresentation, CodeStatsAggregatorTests를 추가해 세션·메시지·토큰·연속일·모델 사용량 통계를 집계하고 EmptyState에서 개요/모델 히스토리 대시보드를 렌더링하도록 구현했습니다.

ChatWindow.xaml, TranscriptRendering, TopicPresetPresentation, ConversationManagementPresentation, OverlaySettingsPresentation, xaml.cs에 UpdateCodeStatsVisibility 연결을 추가해 탭 전환, 첫 메시지 전송, 프리셋 선택, 대화 삭제 시 빈화면과 대시보드가 일관되게 전환되도록 수정했습니다.

README.md와 docs/DEVELOPMENT.md에 2026-04-16 08:10 (KST) 기준 병합 이력과 검증 결과를 반영했습니다.

검증: verify_code_stats_merge 빌드 경고 0 / 오류 0, verify_code_stats_merge_tests 대상 테스트 56개 통과

README.md

@@ -1,5 +1,14 @@
 # AX Commander
 
+- Update: 2026-04-16 08:10 (KST)
+- Merged the external work-log changes recorded in `E:\AX Copilot - Claude\.claude\worktrees\vibrant-mendeleev\docs\WORK_LOG_2026-04-15_22h_to_2026-04-16.md` into the local Code tab implementation.
+- The current branch already superseded the external context-persistence track in `AxAgentExecutionEngine` and `AgentQueryContextBuilder`, so the merge focused on the missing Code stats surface instead of overwriting the newer local context pipeline.
+- Added `src/AxCopilot/Models/CodeStatsSummary.cs`, `src/AxCopilot/Services/CodeStatsAggregator.cs`, `src/AxCopilot/Views/ChatWindow.CodeStatsPresentation.cs`, and `src/AxCopilot.Tests/Services/CodeStatsAggregatorTests.cs` to render a `/stats`-style Code dashboard with session count, stored message count, total tokens, streaks, a 12-week activity heatmap, and per-model token usage history.
+- `src/AxCopilot/Views/ChatWindow.xaml`, `src/AxCopilot/Views/ChatWindow.TranscriptRendering.cs`, `src/AxCopilot/Views/ChatWindow.xaml.cs`, `src/AxCopilot/Views/ChatWindow.TopicPresetPresentation.cs`, `src/AxCopilot/Views/ChatWindow.ConversationManagementPresentation.cs`, and `src/AxCopilot/Views/ChatWindow.OverlaySettingsPresentation.cs` now keep the dashboard synchronized with EmptyState visibility when the user switches tabs, clears conversations, picks presets, or starts the first Code message.
+- Verification:
+  - `dotnet build src/AxCopilot/AxCopilot.csproj -c Release -v minimal -p:OutputPath=bin\\verify_code_stats_merge\\ -p:IntermediateOutputPath=obj\\verify_code_stats_merge\\` warning 0 / error 0
+  - `dotnet test src/AxCopilot.Tests/AxCopilot.Tests.csproj -c Release -v minimal --filter "CodeStatsAggregatorTests|AxAgentExecutionEngineTests|AgentQueryContextBuilderTests|ContextCondenserTests|SettingsServiceTests" -p:OutputPath=bin\\verify_code_stats_merge_tests\\ -p:IntermediateOutputPath=obj\\verify_code_stats_merge_tests\\` passed 56
+
 - Update: 2026-04-16 07:40 (KST)
 - Code tab context reliability was hardened to keep durable tool transcript history, auto-resolve the context budget when `MaxContextTokens = 0`, restore recent compacted tool snippets after boundary compaction, and deduplicate repeated system prompts before each loop request.
 - `src/AxCopilot/Services/Agent/AxAgentExecutionEngine.cs` now preserves full `ChatMessage` metadata during turn cloning and syncs structured tool-use and tool-result transcript messages back into `conversation.Messages`, so the next turn and persisted history keep the same repair context.

docs/DEVELOPMENT.md

@@ -1,4 +1,12 @@
-업데이트: 2026-04-15 20:19 (KST)
+업데이트: 2026-04-16 08:10 (KST)
+- 외부 작업 로그 E:\AX Copilot - Claude\.claude\worktrees\vibrant-mendeleev\docs\WORK_LOG_2026-04-15_22h_to_2026-04-16.md 기준으로 Code 탭 병합 검토를 수행했습니다. AxAgentExecutionEngine, AgentQueryContextBuilder 쪽 컨텍스트 영속화는 현재 브랜치가 이미 더 앞선 구조를 갖고 있어 덮어쓰지 않았고, 누락되어 있던 Code 사용량 대시보드만 선택적으로 병합했습니다.
+- src/AxCopilot/Models/CodeStatsSummary.cs, src/AxCopilot/Services/CodeStatsAggregator.cs를 추가해 AgentStatsService 기록과 저장된 Code 대화 메시지 수를 기간별(전체/30일/7일)로 집계하도록 했습니다. 최근 12주 히트맵, 현재/최장 연속 일수, 최다 사용 시간, 즐겨 쓰는 모델, 모델별 in/out 토큰 합계를 모두 집계합니다.
+- src/AxCopilot/Views/ChatWindow.xaml, src/AxCopilot/Views/ChatWindow.CodeStatsPresentation.cs를 추가/확장해 Code 탭 빈 화면에서만 보이는 /stats 스타일 대시보드를 렌더링하도록 했습니다. 대시보드는 8개 요약 카드, 히트맵, 모델 스택 차트, 범위 필터, 내부 탭(개요/모델)을 포함합니다.
+- src/AxCopilot/Views/ChatWindow.TranscriptRendering.cs, src/AxCopilot/Views/ChatWindow.xaml.cs, src/AxCopilot/Views/ChatWindow.TopicPresetPresentation.cs, src/AxCopilot/Views/ChatWindow.ConversationManagementPresentation.cs, src/AxCopilot/Views/ChatWindow.OverlaySettingsPresentation.cs는 UpdateCodeStatsVisibility()를 빈 상태 전환 지점에 연결해 탭 전환, 첫 메시지 전송, 프리셋 선택, 대화 삭제/전체 삭제 상황에서도 대시보드와 EmptyState가 엇갈리지 않도록 맞췄습니다.
+- 테스트: src/AxCopilot.Tests/Services/CodeStatsAggregatorTests.cs
+- 검증: dotnet build src/AxCopilot/AxCopilot.csproj -c Release -v minimal -p:OutputPath=bin\\verify_code_stats_merge\\ -p:IntermediateOutputPath=obj\\verify_code_stats_merge\\ 경고 0 / 오류 0
+- 검증: dotnet test src/AxCopilot.Tests/AxCopilot.Tests.csproj -c Release -v minimal --filter "CodeStatsAggregatorTests|AxAgentExecutionEngineTests|AgentQueryContextBuilderTests|ContextCondenserTests|SettingsServiceTests" -p:OutputPath=bin\\verify_code_stats_merge_tests\\ -p:IntermediateOutputPath=obj\\verify_code_stats_merge_tests\\ 통과 56
+업데이트: 2026-04-15 20:19 (KST)
 - AX Agent 반복 상한을 500으로 확장했습니다. `src/AxCopilot/ViewModels/SettingsViewModel.cs`의 `MaxAgentIterations` 클램프를 `1~500`으로 올리고, `src/AxCopilot/Views/SettingsWindow.xaml`의 슬라이더/힌트 문구도 같은 범위로 맞췄습니다.
 - `src/AxCopilot/Views/ChatWindow.xaml`, `src/AxCopilot/Views/ChatWindow.OverlaySettingsPresentation.cs`, `src/AxCopilot/Views/AgentSettingsWindow.xaml.cs`도 함께 수정해 Code 탭 오버레이와 별도 에이전트 설정창이 여전히 100 또는 200에 묶이지 않도록 범위를 통일했습니다.
 - 검증: `dotnet build src/AxCopilot/AxCopilot.csproj -c Release -v minimal -p:OutputPath=bin\\verify_max_agent_iterations_500\\ -p:IntermediateOutputPath=obj\\verify_max_agent_iterations_500\\` 경고 0 / 오류 0
@@ -1892,3 +1900,11 @@ UI ?遺우쁽????域뱀뮆???귐뗫솯?醫딆춦 ???袁る퓮 ?臾믩씜 ??疫
   - `dotnet build src/AxCopilot/AxCopilot.csproj -c Release -v minimal -p:OutputPath=bin\\verify_context_reliability_followup\\ -p:IntermediateOutputPath=obj\\verify_context_reliability_followup\\` 경고 0 / 오류 0
   - `dotnet test src/AxCopilot.Tests/AxCopilot.Tests.csproj -c Release -v minimal --filter "AxAgentExecutionEngineTests|AgentQueryContextBuilderTests|ContextCondenserTests|SettingsServiceTests|AgentLoopDiagnosticsFormatterTests" -p:OutputPath=bin\\verify_context_reliability_followup_tests\\ -p:IntermediateOutputPath=obj\\verify_context_reliability_followup_tests\\` 통과 50
   - `dotnet test src/AxCopilot.Tests/AxCopilot.Tests.csproj -c Release -v minimal --filter "AgentLoopQueryAssemblyServiceTests|AgentLoopPreLlmStageServiceTests|AgentLoopLlmRequestPreparationServiceTests|AgentMessageInvariantHelperTests|CodeTaskWorkingSetServiceTests|AgentLoopE2ETests" -p:OutputPath=bin\\verify_context_reliability_followup_tests2\\ -p:IntermediateOutputPath=obj\\verify_context_reliability_followup_tests2\\` 통과 38
+업데이트: 2026-04-16 08:10 (KST)
+- 외부 작업 로그 `E:\AX Copilot - Claude\.claude\worktrees\vibrant-mendeleev\docs\WORK_LOG_2026-04-15_22h_to_2026-04-16.md` 기준으로 Code 탭 병합 검토를 수행했습니다. `AxAgentExecutionEngine`, `AgentQueryContextBuilder` 쪽 컨텍스트 영속화는 현재 브랜치가 이미 더 앞선 구조를 갖고 있어 덮어쓰지 않았고, 누락되어 있던 Code 사용량 대시보드만 선택적으로 병합했습니다.
+- `src/AxCopilot/Models/CodeStatsSummary.cs`, `src/AxCopilot/Services/CodeStatsAggregator.cs`를 추가해 `AgentStatsService` 기록과 저장된 Code 대화 메시지 수를 기간별(`전체/30일/7일`)로 집계하도록 했습니다. 최근 12주 히트맵, 현재/최장 연속 일수, 최다 사용 시간, 즐겨 쓰는 모델, 모델별 in/out 토큰 합계를 모두 집계합니다.
+- `src/AxCopilot/Views/ChatWindow.xaml`, `src/AxCopilot/Views/ChatWindow.CodeStatsPresentation.cs`를 추가/확장해 Code 탭 빈 화면에서만 보이는 `/stats` 스타일 대시보드를 렌더링하도록 했습니다. 대시보드는 8개 요약 카드, 히트맵, 모델 스택 차트, 범위 필터, 내부 탭(`개요/모델`)을 포함합니다.
+- `src/AxCopilot/Views/ChatWindow.TranscriptRendering.cs`, `src/AxCopilot/Views/ChatWindow.xaml.cs`, `src/AxCopilot/Views/ChatWindow.TopicPresetPresentation.cs`, `src/AxCopilot/Views/ChatWindow.ConversationManagementPresentation.cs`, `src/AxCopilot/Views/ChatWindow.OverlaySettingsPresentation.cs`는 `UpdateCodeStatsVisibility()`를 빈 상태 전환 지점에 연결해 탭 전환, 첫 메시지 전송, 프리셋 선택, 대화 삭제/전체 삭제 상황에서도 대시보드와 EmptyState가 엇갈리지 않도록 맞췄습니다.
+- 테스트: `src/AxCopilot.Tests/Services/CodeStatsAggregatorTests.cs`
+- 검증: `dotnet build src/AxCopilot/AxCopilot.csproj -c Release -v minimal -p:OutputPath=bin\\verify_code_stats_merge\\ -p:IntermediateOutputPath=obj\\verify_code_stats_merge\\` 경고 0 / 오류 0
+- 검증: `dotnet test src/AxCopilot.Tests/AxCopilot.Tests.csproj -c Release -v minimal --filter "CodeStatsAggregatorTests|AxAgentExecutionEngineTests|AgentQueryContextBuilderTests|ContextCondenserTests|SettingsServiceTests" -p:OutputPath=bin\\verify_code_stats_merge_tests\\ -p:IntermediateOutputPath=obj\\verify_code_stats_merge_tests\\` 통과 56

src/AxCopilot.Tests/Services/CodeStatsAggregatorTests.cs

@@ -0,0 +1,191 @@
+using AxCopilot.Models;
+using AxCopilot.Services;
+using FluentAssertions;
+using Xunit;
+
+namespace AxCopilot.Tests.Services;
+
+/// <summary>
+/// Tests for the pure helper logic inside CodeStatsAggregator.
+/// </summary>
+public class CodeStatsAggregatorTests
+{
+    [Fact]
+    public void ComputeStreaks_ReturnsZeroWhenNoActivity()
+    {
+        var (current, longest) = CodeStatsAggregator.ComputeStreaks(
+            Array.Empty<DateTime>(),
+            new DateTime(2026, 4, 16));
+
+        current.Should().Be(0);
+        longest.Should().Be(0);
+    }
+
+    [Fact]
+    public void ComputeStreaks_CurrentStreakWalksBackFromToday()
+    {
+        var today = new DateTime(2026, 4, 16);
+        var dates = new[]
+        {
+            today,
+            today.AddDays(-1),
+            today.AddDays(-2),
+            today.AddDays(-4),
+        };
+
+        var (current, longest) = CodeStatsAggregator.ComputeStreaks(dates, today);
+
+        current.Should().Be(3);
+        longest.Should().Be(3);
+    }
+
+    [Fact]
+    public void ComputeStreaks_CurrentStreakIsZeroWhenTodayMissing()
+    {
+        var today = new DateTime(2026, 4, 16);
+        var dates = new[]
+        {
+            today.AddDays(-1),
+            today.AddDays(-2),
+            today.AddDays(-3),
+        };
+
+        var (current, _) = CodeStatsAggregator.ComputeStreaks(dates, today);
+
+        current.Should().Be(0);
+    }
+
+    [Fact]
+    public void ComputeStreaks_LongestStreakFindsMaxConsecutiveRun()
+    {
+        var anchor = new DateTime(2026, 4, 16);
+        var dates = new[]
+        {
+            anchor.AddDays(-20),
+            anchor.AddDays(-19),
+            anchor.AddDays(-15),
+            anchor.AddDays(-14),
+            anchor.AddDays(-13),
+            anchor.AddDays(-12),
+            anchor.AddDays(-11),
+            anchor,
+        };
+
+        var (current, longest) = CodeStatsAggregator.ComputeStreaks(dates, anchor);
+
+        current.Should().Be(1);
+        longest.Should().Be(5);
+    }
+
+    [Fact]
+    public void ComputeStreaks_DuplicateDatesAreDeduplicated()
+    {
+        var today = new DateTime(2026, 4, 16);
+        var dates = new[]
+        {
+            today,
+            today.AddHours(2),
+            today.AddHours(8),
+            today.AddDays(-1),
+        };
+
+        var (current, longest) = CodeStatsAggregator.ComputeStreaks(dates, today);
+
+        current.Should().Be(2);
+        longest.Should().Be(2);
+    }
+
+    [Fact]
+    public void Aggregate_EmptyData_ReturnsEmptySummaryWithHeatmapPlaceholders()
+    {
+        CodeStatsAggregator.InvalidateCache();
+        var summary = CodeStatsAggregator.Aggregate(CodeStatsPeriod.Last30Days, storage: null, bypassCache: true);
+
+        summary.Should().NotBeNull();
+        summary.Period.Should().Be(CodeStatsPeriod.Last30Days);
+        summary.Heatmap.Should().NotBeEmpty();
+        summary.MessagesCount.Should().Be(0);
+    }
+
+    [Fact]
+    public void CountStoredCodeMessages_ReturnsZeroWhenStorageIsNull()
+    {
+        var count = CodeStatsAggregator.CountStoredCodeMessages(storage: null);
+        count.Should().Be(0);
+    }
+
+    [Fact]
+    public void CountStoredCodeMessages_FiltersToCodeTabAndSumsMessages()
+    {
+        var fake = new FakeChatStorage();
+        fake.Add(tab: "Code", messages: 4);
+        fake.Add(tab: "Cowork", messages: 7);
+        fake.Add(tab: "Code", messages: 3);
+        fake.Add(tab: "Chat", messages: 11);
+
+        var count = CodeStatsAggregator.CountStoredCodeMessages(fake);
+
+        count.Should().Be(7);
+    }
+
+    private sealed class FakeChatStorage : IChatStorageService
+    {
+        private readonly List<ChatConversation> _store = new();
+
+        public void Add(string tab, int messages)
+        {
+            var id = Guid.NewGuid().ToString("N");
+            var conversation = new ChatConversation { Id = id, Tab = tab };
+            for (var i = 0; i < messages; i++)
+            {
+                conversation.Messages.Add(new ChatMessage
+                {
+                    Role = i % 2 == 0 ? "user" : "assistant",
+                    Content = $"msg-{i}",
+                });
+            }
+
+            _store.Add(conversation);
+        }
+
+        public void Save(ChatConversation conversation) { }
+
+        public ChatConversation? Load(string id) => _store.FirstOrDefault(c => c.Id == id);
+
+        public Task<ChatConversation?> LoadAsync(string id) => Task.FromResult<ChatConversation?>(Load(id));
+
+        public List<ChatConversation> LoadAllMeta()
+        {
+            return _store.Select(c => new ChatConversation
+            {
+                Id = c.Id,
+                Tab = c.Tab,
+                Title = c.Title,
+                CreatedAt = c.CreatedAt,
+                UpdatedAt = c.UpdatedAt,
+                Messages = new(),
+            }).ToList();
+        }
+
+        public void InvalidateMetaCache() { }
+
+        public void UpdateMetaCache(ChatConversation conv) { }
+
+        public void RemoveFromMetaCache(string id) { }
+
+        public void Delete(string id) => _store.RemoveAll(c => c.Id == id);
+
+        public int DeleteAll()
+        {
+            var count = _store.Count;
+            _store.Clear();
+            return count;
+        }
+
+        public int DeleteAllByTab(string tab) => _store.RemoveAll(c => c.Tab == tab);
+
+        public int PurgeExpired(int retentionDays) => 0;
+
+        public int PurgeForDiskSpace(double threshold = 0.98) => 0;
+    }
+}

src/AxCopilot/Models/CodeStatsSummary.cs

@@ -0,0 +1,63 @@
+namespace AxCopilot.Models;
+
+/// <summary>
+/// Period filter for the Code tab usage dashboard.
+/// Mirrors the "All / 30d / 7d" controls shown in the reference stats view.
+/// </summary>
+public enum CodeStatsPeriod
+{
+    /// <summary>Aggregate over every record on disk.</summary>
+    All = 0,
+    /// <summary>Aggregate over the last 30 days.</summary>
+    Last30Days = 30,
+    /// <summary>Aggregate over the last 7 days.</summary>
+    Last7Days = 7,
+}
+
+/// <summary>
+/// One day in the activity heatmap.
+/// IntensityLevel is 0..4 where 0 means "no activity".
+/// </summary>
+public sealed record CodeStatsHeatmapCell(DateTime Date, long Tokens, int IntensityLevel);
+
+/// <summary>One model bucket within a single day of the model chart.</summary>
+public sealed record CodeStatsModelDailyTokens(string Model, long Tokens);
+
+/// <summary>One day in the stacked model chart.</summary>
+public sealed record CodeStatsDailyModelStack(DateTime Date, IReadOnlyList<CodeStatsModelDailyTokens> Models);
+
+/// <summary>
+/// Per-model aggregate row shown beneath the model stacked bar chart.
+/// SharePercent is 0..100.
+/// </summary>
+public sealed record CodeStatsModelTotal(
+    string Model,
+    long InTokens,
+    long OutTokens,
+    double SharePercent);
+
+/// <summary>
+/// Summary model used by the Code tab usage dashboard.
+/// </summary>
+public sealed record CodeStatsSummary
+{
+    public int SessionsCount { get; init; }
+    public int MessagesCount { get; init; }
+    public long TotalTokens { get; init; }
+    public int ActiveDays { get; init; }
+    public int CurrentStreak { get; init; }
+    public int LongestStreak { get; init; }
+    public int? MostActiveHour { get; init; }
+    public string? FavoriteModel { get; init; }
+    public IReadOnlyList<CodeStatsHeatmapCell> Heatmap { get; init; } = Array.Empty<CodeStatsHeatmapCell>();
+    public IReadOnlyList<CodeStatsDailyModelStack> ModelStack { get; init; } = Array.Empty<CodeStatsDailyModelStack>();
+    public IReadOnlyList<CodeStatsModelTotal> ModelTotals { get; init; } = Array.Empty<CodeStatsModelTotal>();
+    public CodeStatsPeriod Period { get; init; }
+    public DateTime ComputedAtUtc { get; init; }
+
+    public static CodeStatsSummary Empty(CodeStatsPeriod period) => new()
+    {
+        Period = period,
+        ComputedAtUtc = DateTime.UtcNow,
+    };
+}

src/AxCopilot/Services/CodeStatsAggregator.cs

@@ -0,0 +1,270 @@
+using AxCopilot.Models;
+
+namespace AxCopilot.Services;
+
+/// <summary>
+/// Aggregates Code tab usage statistics for the EmptyState dashboard.
+/// Data comes from AgentStatsService session records and stored conversations.
+/// </summary>
+public static class CodeStatsAggregator
+{
+    private const string CodeTabKey = "Code";
+    private const int HeatmapDays = 84;
+    private static readonly TimeSpan CacheTtl = TimeSpan.FromSeconds(60);
+    private static readonly object CacheLock = new();
+    private static readonly Dictionary<CodeStatsPeriod, (CodeStatsSummary Summary, DateTime ExpiresAtUtc)> Cache = new();
+
+    public static CodeStatsSummary Aggregate(CodeStatsPeriod period, IChatStorageService? storage = null, bool bypassCache = false)
+    {
+        if (!bypassCache)
+        {
+            lock (CacheLock)
+            {
+                if (Cache.TryGetValue(period, out var cached) && cached.ExpiresAtUtc > DateTime.UtcNow)
+                    return cached.Summary;
+            }
+        }
+
+        var summary = AggregateInternal(period, storage);
+        lock (CacheLock)
+        {
+            Cache[period] = (summary, DateTime.UtcNow.Add(CacheTtl));
+        }
+
+        return summary;
+    }
+
+    public static void InvalidateCache()
+    {
+        lock (CacheLock)
+        {
+            Cache.Clear();
+        }
+    }
+
+    private static CodeStatsSummary AggregateInternal(CodeStatsPeriod period, IChatStorageService? storage)
+    {
+        var days = (int)period;
+        var records = AgentStatsService.LoadRecords(days)
+            .Where(record => string.Equals(record.Tab, CodeTabKey, StringComparison.OrdinalIgnoreCase))
+            .ToList();
+
+        if (records.Count == 0)
+        {
+            return CodeStatsSummary.Empty(period) with
+            {
+                MessagesCount = CountStoredCodeMessages(storage),
+                Heatmap = BuildEmptyHeatmap(),
+            };
+        }
+
+        var sessionsCount = records.Count;
+        var totalIn = records.Sum(record => (long)record.InputTokens);
+        var totalOut = records.Sum(record => (long)record.OutputTokens);
+        var totalTokens = totalIn + totalOut;
+
+        var activeDates = records
+            .Select(record => record.Timestamp.Date)
+            .Distinct()
+            .OrderBy(date => date)
+            .ToList();
+
+        var (currentStreak, longestStreak) = ComputeStreaks(activeDates, DateTime.Today);
+        var mostActiveHour = records
+            .GroupBy(record => record.Timestamp.Hour)
+            .Select(group => new { Hour = group.Key, Count = group.Count() })
+            .OrderByDescending(item => item.Count)
+            .ThenBy(item => item.Hour)
+            .FirstOrDefault()
+            ?.Hour;
+
+        var favoriteModel = records
+            .Where(record => !string.IsNullOrWhiteSpace(record.Model))
+            .GroupBy(record => record.Model)
+            .Select(group => new
+            {
+                Model = group.Key,
+                Tokens = group.Sum(record => (long)record.InputTokens + record.OutputTokens),
+            })
+            .OrderByDescending(item => item.Tokens)
+            .ThenBy(item => item.Model, StringComparer.Ordinal)
+            .FirstOrDefault()
+            ?.Model;
+
+        return new CodeStatsSummary
+        {
+            SessionsCount = sessionsCount,
+            MessagesCount = CountStoredCodeMessages(storage),
+            TotalTokens = totalTokens,
+            ActiveDays = activeDates.Count,
+            CurrentStreak = currentStreak,
+            LongestStreak = longestStreak,
+            MostActiveHour = mostActiveHour,
+            FavoriteModel = favoriteModel,
+            Heatmap = BuildHeatmap(records, DateTime.Today),
+            ModelStack = BuildModelStack(records),
+            ModelTotals = BuildModelTotals(records, totalTokens),
+            Period = period,
+            ComputedAtUtc = DateTime.UtcNow,
+        };
+    }
+
+    internal static int CountStoredCodeMessages(IChatStorageService? storage)
+    {
+        if (storage == null)
+            return 0;
+
+        try
+        {
+            var metas = storage.LoadAllMeta();
+            if (metas.Count == 0)
+                return 0;
+
+            var total = 0;
+            foreach (var meta in metas)
+            {
+                if (!string.Equals(meta.Tab, CodeTabKey, StringComparison.OrdinalIgnoreCase))
+                    continue;
+
+                var fullConversation = storage.Load(meta.Id);
+                total += fullConversation?.Messages?.Count ?? 0;
+            }
+
+            return total;
+        }
+        catch
+        {
+            return 0;
+        }
+    }
+
+    internal static (int Current, int Longest) ComputeStreaks(IEnumerable<DateTime> activeDates, DateTime today)
+    {
+        var dateSet = new HashSet<DateTime>(activeDates.Select(date => date.Date));
+        if (dateSet.Count == 0)
+            return (0, 0);
+
+        var current = 0;
+        var cursor = today.Date;
+        while (dateSet.Contains(cursor))
+        {
+            current++;
+            cursor = cursor.AddDays(-1);
+        }
+
+        var longest = 0;
+        var run = 0;
+        DateTime? previous = null;
+        foreach (var date in dateSet.OrderBy(date => date))
+        {
+            if (previous.HasValue && date == previous.Value.AddDays(1))
+                run++;
+            else
+                run = 1;
+
+            if (run > longest)
+                longest = run;
+
+            previous = date;
+        }
+
+        return (current, longest);
+    }
+
+    private static IReadOnlyList<CodeStatsHeatmapCell> BuildHeatmap(IEnumerable<AgentStatsService.AgentSessionRecord> records, DateTime today)
+    {
+        var perDate = records
+            .GroupBy(record => record.Timestamp.Date)
+            .ToDictionary(group => group.Key, group => group.Sum(record => (long)record.InputTokens + record.OutputTokens));
+
+        var cells = new List<CodeStatsHeatmapCell>(HeatmapDays);
+        for (var offset = HeatmapDays - 1; offset >= 0; offset--)
+        {
+            var date = today.Date.AddDays(-offset);
+            var tokens = perDate.GetValueOrDefault(date, 0L);
+            cells.Add(new CodeStatsHeatmapCell(date, tokens, 0));
+        }
+
+        var nonZero = cells
+            .Where(cell => cell.Tokens > 0)
+            .Select(cell => cell.Tokens)
+            .OrderBy(value => value)
+            .ToList();
+
+        if (nonZero.Count == 0)
+            return cells;
+
+        long Quartile(double pct)
+        {
+            if (nonZero.Count == 1)
+                return nonZero[0];
+
+            var index = (int)Math.Floor((nonZero.Count - 1) * pct);
+            return nonZero[Math.Clamp(index, 0, nonZero.Count - 1)];
+        }
+
+        var q1 = Quartile(0.25);
+        var q2 = Quartile(0.50);
+        var q3 = Quartile(0.75);
+
+        return cells
+            .Select(cell => cell with
+            {
+                IntensityLevel = cell.Tokens <= 0 ? 0
+                    : cell.Tokens <= q1 ? 1
+                    : cell.Tokens <= q2 ? 2
+                    : cell.Tokens <= q3 ? 3
+                    : 4,
+            })
+            .ToList();
+    }
+
+    private static IReadOnlyList<CodeStatsHeatmapCell> BuildEmptyHeatmap()
+    {
+        var today = DateTime.Today;
+        var cells = new List<CodeStatsHeatmapCell>(HeatmapDays);
+        for (var offset = HeatmapDays - 1; offset >= 0; offset--)
+        {
+            cells.Add(new CodeStatsHeatmapCell(today.AddDays(-offset), 0L, 0));
+        }
+
+        return cells;
+    }
+
+    private static IReadOnlyList<CodeStatsDailyModelStack> BuildModelStack(IEnumerable<AgentStatsService.AgentSessionRecord> records)
+    {
+        return records
+            .Where(record => !string.IsNullOrWhiteSpace(record.Model))
+            .GroupBy(record => record.Timestamp.Date)
+            .OrderBy(group => group.Key)
+            .Select(group => new CodeStatsDailyModelStack(
+                group.Key,
+                group.GroupBy(record => record.Model)
+                    .Select(modelGroup => new CodeStatsModelDailyTokens(
+                        modelGroup.Key,
+                        modelGroup.Sum(record => (long)record.InputTokens + record.OutputTokens)))
+                    .OrderByDescending(item => item.Tokens)
+                    .ToList()))
+            .ToList();
+    }
+
+    private static IReadOnlyList<CodeStatsModelTotal> BuildModelTotals(
+        IEnumerable<AgentStatsService.AgentSessionRecord> records,
+        long totalTokens)
+    {
+        return records
+            .Where(record => !string.IsNullOrWhiteSpace(record.Model))
+            .GroupBy(record => record.Model)
+            .Select(group =>
+            {
+                var inTokens = group.Sum(record => (long)record.InputTokens);
+                var outTokens = group.Sum(record => (long)record.OutputTokens);
+                var combined = inTokens + outTokens;
+                var share = totalTokens > 0 ? combined * 100.0 / totalTokens : 0.0;
+                return new CodeStatsModelTotal(group.Key, inTokens, outTokens, Math.Round(share, 1));
+            })
+            .OrderByDescending(item => item.InTokens + item.OutTokens)
+            .ThenBy(item => item.Model, StringComparer.Ordinal)
+            .ToList();
+    }
+}

src/AxCopilot/Views/ChatWindow.CodeStatsPresentation.cs

@@ -0,0 +1,517 @@
+using System.Globalization;
+using System.Windows;
+using System.Windows.Controls;
+using System.Windows.Input;
+using System.Windows.Media;
+using System.Windows.Shapes;
+using AxCopilot.Models;
+using AxCopilot.Services;
+
+namespace AxCopilot.Views;
+
+/// <summary>
+/// Renders the Code tab usage dashboard inside the EmptyState surface when the
+/// current Code conversation has no transcript yet.
+/// </summary>
+public partial class ChatWindow
+{
+    private static readonly string[] ModelPaletteHex =
+    {
+        "#A78BFA",
+        "#3B82F6",
+        "#10B981",
+        "#F59E0B",
+        "#EC4899",
+        "#06B6D4",
+        "#F97316",
+        "#8B5CF6",
+    };
+
+    private CodeStatsPeriod _codeStatsPeriod = CodeStatsPeriod.Last30Days;
+    private string _codeStatsInnerTab = "overview";
+    private bool _codeStatsInitialized;
+    private bool _codeStatsRefreshInFlight;
+
+    private void InitializeCodeStats()
+    {
+        if (_codeStatsInitialized)
+            return;
+
+        _codeStatsInitialized = true;
+        SetCodeStatsInnerTabVisuals();
+        SetCodeStatsRangeVisuals();
+    }
+
+    private void UpdateCodeStatsVisibility()
+    {
+        if (CodeStatsDashboardScroll == null || EmptyStateCenterStack == null)
+            return;
+
+        var isCodeTab = string.Equals(_activeTab, "Code", StringComparison.OrdinalIgnoreCase);
+        var hasMessages = (_currentConversation?.Messages?.Count ?? 0) > 0;
+        var emptyVisible = EmptyState != null && EmptyState.Visibility == Visibility.Visible;
+        var shouldShowDashboard = isCodeTab && !hasMessages && emptyVisible;
+
+        CodeStatsDashboardScroll.Visibility = shouldShowDashboard ? Visibility.Visible : Visibility.Collapsed;
+        EmptyStateCenterStack.Visibility = shouldShowDashboard ? Visibility.Collapsed : Visibility.Visible;
+        ApplyMascotDashboardLayout(shouldShowDashboard);
+
+        if (shouldShowDashboard)
+        {
+            InitializeCodeStats();
+            _ = RefreshCodeStatsAsync();
+        }
+    }
+
+    private void ApplyMascotDashboardLayout(bool dashboardActive)
+    {
+        if (MascotImage == null || MascotScale == null)
+            return;
+
+        if (dashboardActive)
+        {
+            MascotScale.ScaleX = 0.55;
+            MascotScale.ScaleY = 0.55;
+            MascotImage.Opacity = 0.65;
+        }
+        else
+        {
+            MascotScale.ScaleX = 1.0;
+            MascotScale.ScaleY = 1.0;
+            MascotImage.Opacity = 0.92;
+        }
+    }
+
+    private async Task RefreshCodeStatsAsync()
+    {
+        if (_codeStatsRefreshInFlight)
+            return;
+
+        _codeStatsRefreshInFlight = true;
+        try
+        {
+            var period = _codeStatsPeriod;
+            var storage = _storage;
+            var summary = await Task.Run(() => CodeStatsAggregator.Aggregate(period, storage));
+            await Dispatcher.InvokeAsync(() => RenderCodeStats(summary));
+        }
+        catch (Exception ex)
+        {
+            LogService.Debug($"[CodeStats] refresh failed: {ex.Message}");
+        }
+        finally
+        {
+            _codeStatsRefreshInFlight = false;
+        }
+    }
+
+    private void RenderCodeStats(CodeStatsSummary summary)
+    {
+        if (CodeStatsDashboard == null)
+            return;
+
+        RenderStatsCards(summary);
+        RenderStatsHeatmap(summary);
+        RenderStatsFunFact(summary);
+        RenderStatsModelPanel(summary);
+        ApplyInnerTabVisibility();
+    }
+
+    private void RenderStatsCards(CodeStatsSummary summary)
+    {
+        if (StatsCardGrid == null)
+            return;
+
+        StatsCardGrid.Children.Clear();
+        StatsCardGrid.Children.Add(MakeStatsCard("\uE9D9", "세션", FormatNumber(summary.SessionsCount), "#A78BFA"));
+        StatsCardGrid.Children.Add(MakeStatsCard("\uE8BD", "메시지", FormatNumber(summary.MessagesCount), "#3B82F6"));
+        StatsCardGrid.Children.Add(MakeStatsCard("\uE7C8", "총 토큰", FormatTokens(summary.TotalTokens), "#10B981"));
+        StatsCardGrid.Children.Add(MakeStatsCard("\uE787", "활성 일수", FormatNumber(summary.ActiveDays), "#F59E0B"));
+        StatsCardGrid.Children.Add(MakeStatsCard("\uE945", "현재 연속 일수", $"{summary.CurrentStreak}일", "#EC4899"));
+        StatsCardGrid.Children.Add(MakeStatsCard("\uE735", "최장 연속 일수", $"{summary.LongestStreak}일", "#F97316"));
+        StatsCardGrid.Children.Add(MakeStatsCard("\uE823", "최다 사용 시간", FormatHour(summary.MostActiveHour), "#06B6D4"));
+        StatsCardGrid.Children.Add(MakeStatsCard("\uE790", "가장 많이 쓴 모델", FormatModelName(summary.FavoriteModel), "#8B5CF6"));
+    }
+
+    private Border MakeStatsCard(string icon, string label, string value, string colorHex)
+    {
+        var background = TryFindResource("ItemBackground") as Brush
+                         ?? new SolidColorBrush(Color.FromRgb(0x1F, 0x1F, 0x2E));
+        var foreground = TryFindResource("PrimaryText") as Brush ?? Brushes.White;
+        var secondary = TryFindResource("SecondaryText") as Brush ?? Brushes.Gray;
+        var border = TryFindResource("BorderColor") as Brush ?? Brushes.DimGray;
+        var color = (Color)ColorConverter.ConvertFromString(colorHex);
+
+        var card = new Border
+        {
+            Background = background,
+            BorderBrush = border,
+            BorderThickness = new Thickness(1),
+            CornerRadius = new CornerRadius(10),
+            Padding = new Thickness(14, 12, 14, 12),
+            Margin = new Thickness(0, 0, 8, 8),
+        };
+
+        var stack = new StackPanel();
+        stack.Children.Add(new TextBlock
+        {
+            Text = label,
+            FontSize = 11,
+            Foreground = secondary,
+            Margin = new Thickness(0, 0, 0, 6),
+        });
+
+        var valueRow = new StackPanel { Orientation = Orientation.Horizontal };
+        valueRow.Children.Add(new TextBlock
+        {
+            Text = icon,
+            FontFamily = new FontFamily("Segoe MDL2 Assets"),
+            FontSize = 14,
+            Foreground = new SolidColorBrush(color),
+            VerticalAlignment = VerticalAlignment.Center,
+            Margin = new Thickness(0, 0, 8, 0),
+        });
+        valueRow.Children.Add(new TextBlock
+        {
+            Text = value,
+            FontSize = 18,
+            FontWeight = FontWeights.SemiBold,
+            Foreground = foreground,
+            VerticalAlignment = VerticalAlignment.Center,
+            TextTrimming = TextTrimming.CharacterEllipsis,
+        });
+
+        stack.Children.Add(valueRow);
+        card.Child = stack;
+        card.ToolTip = $"{label}: {value}";
+        return card;
+    }
+
+    private void RenderStatsHeatmap(CodeStatsSummary summary)
+    {
+        if (StatsHeatmapCanvas == null)
+            return;
+
+        StatsHeatmapCanvas.Children.Clear();
+
+        const double cellSize = 14;
+        const double cellGap = 3;
+        const int rows = 7;
+
+        var accent = TryFindResource("AccentColor") as SolidColorBrush
+                     ?? new SolidColorBrush(Color.FromRgb(0x4B, 0x5E, 0xFC));
+        var emptyBackground = TryFindResource("ItemHoverBackground") as Brush
+                              ?? new SolidColorBrush(Color.FromArgb(0x33, 0x80, 0x80, 0x80));
+
+        var cells = summary.Heatmap;
+        if (cells.Count == 0)
+            return;
+
+        var firstWeekday = WeekdayIndex(cells[0].Date);
+        for (var i = 0; i < cells.Count; i++)
+        {
+            var cell = cells[i];
+            var slot = i + firstWeekday;
+            var column = slot / rows;
+            var row = slot % rows;
+
+            var fill = cell.IntensityLevel switch
+            {
+                0 => emptyBackground,
+                1 => MakeAlpha(accent.Color, 0.30),
+                2 => MakeAlpha(accent.Color, 0.55),
+                3 => MakeAlpha(accent.Color, 0.78),
+                _ => new SolidColorBrush(accent.Color) { Opacity = 1.0 },
+            };
+
+            var rectangle = new Rectangle
+            {
+                Width = cellSize,
+                Height = cellSize,
+                Fill = fill,
+                RadiusX = 3,
+                RadiusY = 3,
+                ToolTip = $"{cell.Date:yyyy-MM-dd} · {FormatTokens(cell.Tokens)} tokens",
+            };
+
+            Canvas.SetLeft(rectangle, column * (cellSize + cellGap));
+            Canvas.SetTop(rectangle, row * (cellSize + cellGap));
+            StatsHeatmapCanvas.Children.Add(rectangle);
+        }
+    }
+
+    private static SolidColorBrush MakeAlpha(Color baseColor, double alpha)
+    {
+        var channel = (byte)Math.Clamp((int)(alpha * 255), 0, 255);
+        return new SolidColorBrush(Color.FromArgb(channel, baseColor.R, baseColor.G, baseColor.B));
+    }
+
+    private static int WeekdayIndex(DateTime date)
+        => ((int)date.DayOfWeek + 6) % 7;
+
+    private void RenderStatsFunFact(CodeStatsSummary summary)
+    {
+        if (StatsFooterFunFact == null)
+            return;
+
+        const long ReferenceTokensPerBook = 60_000L;
+        const string ReferenceTitle = "어린 왕자";
+
+        if (summary.TotalTokens < ReferenceTokensPerBook)
+        {
+            StatsFooterFunFact.Visibility = Visibility.Collapsed;
+            return;
+        }
+
+        var ratio = summary.TotalTokens / (double)ReferenceTokensPerBook;
+        StatsFooterFunFact.Text = $"『{ReferenceTitle}』보다 약 {ratio:0}배 많은 토큰을 사용했습니다.";
+        StatsFooterFunFact.Visibility = Visibility.Visible;
+    }
+
+    private void RenderStatsModelPanel(CodeStatsSummary summary)
+    {
+        if (StatsModelStackCanvas == null || StatsModelStackXAxis == null || StatsModelLegend == null)
+            return;
+
+        StatsModelStackCanvas.Children.Clear();
+        StatsModelStackXAxis.Children.Clear();
+        StatsModelLegend.Items.Clear();
+
+        var stack = summary.ModelStack;
+        var totals = summary.ModelTotals;
+        var modelColor = new Dictionary<string, Color>(StringComparer.Ordinal);
+        for (var i = 0; i < totals.Count; i++)
+        {
+            modelColor[totals[i].Model] = (Color)ColorConverter.ConvertFromString(ModelPaletteHex[i % ModelPaletteHex.Length]);
+        }
+
+        if (stack.Count > 0)
+        {
+            var maxDayTotal = Math.Max(1, stack.Max(day => day.Models.Sum(model => model.Tokens)));
+            const double chartHeight = 196;
+            const double chartWidth = 720;
+            const double gap = 2;
+            var barWidth = Math.Max(4, (chartWidth - gap * stack.Count) / Math.Max(1, stack.Count));
+
+            for (var i = 0; i < stack.Count; i++)
+            {
+                var day = stack[i];
+                var x = i * (barWidth + gap);
+                var dayTotal = day.Models.Sum(model => model.Tokens);
+                var dayHeight = (dayTotal / (double)maxDayTotal) * (chartHeight - 4);
+                var cursorY = chartHeight - dayHeight;
+
+                foreach (var slice in day.Models)
+                {
+                    if (slice.Tokens <= 0)
+                        continue;
+
+                    var sliceHeight = (slice.Tokens / (double)dayTotal) * dayHeight;
+                    var color = modelColor.TryGetValue(slice.Model, out var mapped)
+                        ? mapped
+                        : Color.FromRgb(0x88, 0x88, 0x88);
+
+                    var rect = new Rectangle
+                    {
+                        Width = barWidth,
+                        Height = Math.Max(1, sliceHeight),
+                        Fill = new SolidColorBrush(color),
+                        ToolTip = $"{day.Date:yyyy-MM-dd}\n{ShortenModelName(slice.Model)}: {FormatTokens(slice.Tokens)}",
+                    };
+
+                    Canvas.SetLeft(rect, x);
+                    Canvas.SetTop(rect, cursorY);
+                    StatsModelStackCanvas.Children.Add(rect);
+                    cursorY += sliceHeight;
+                }
+
+                if (stack.Count <= 14 || i % 7 == 0)
+                {
+                    var label = new TextBlock
+                    {
+                        Text = day.Date.ToString("M/d", CultureInfo.InvariantCulture),
+                        FontSize = 9,
+                        Foreground = TryFindResource("SecondaryText") as Brush ?? Brushes.Gray,
+                    };
+                    Canvas.SetLeft(label, x);
+                    StatsModelStackXAxis.Children.Add(label);
+                }
+            }
+        }
+
+        foreach (var total in totals)
+        {
+            var color = modelColor.TryGetValue(total.Model, out var mapped)
+                ? mapped
+                : Color.FromRgb(0x88, 0x88, 0x88);
+
+            var row = new StackPanel
+            {
+                Orientation = Orientation.Horizontal,
+                Margin = new Thickness(0, 2, 0, 2),
+            };
+            row.Children.Add(new Rectangle
+            {
+                Width = 12,
+                Height = 12,
+                Fill = new SolidColorBrush(color),
+                RadiusX = 2,
+                RadiusY = 2,
+                Margin = new Thickness(0, 0, 8, 0),
+                VerticalAlignment = VerticalAlignment.Center,
+            });
+            row.Children.Add(new TextBlock
+            {
+                Text = ShortenModelName(total.Model),
+                FontSize = 12,
+                Foreground = TryFindResource("PrimaryText") as Brush ?? Brushes.White,
+                VerticalAlignment = VerticalAlignment.Center,
+            });
+            row.Children.Add(new TextBlock
+            {
+                Text = $"  {FormatTokens(total.InTokens)} in · {FormatTokens(total.OutTokens)} out",
+                FontSize = 11,
+                Foreground = TryFindResource("SecondaryText") as Brush ?? Brushes.Gray,
+                VerticalAlignment = VerticalAlignment.Center,
+                Margin = new Thickness(8, 0, 0, 0),
+            });
+            row.Children.Add(new TextBlock
+            {
+                Text = $"  {total.SharePercent.ToString("0.0", CultureInfo.InvariantCulture)}%",
+                FontSize = 11,
+                FontWeight = FontWeights.SemiBold,
+                Foreground = TryFindResource("PrimaryText") as Brush ?? Brushes.White,
+                VerticalAlignment = VerticalAlignment.Center,
+                Margin = new Thickness(8, 0, 0, 0),
+            });
+            StatsModelLegend.Items.Add(row);
+        }
+    }
+
+    private void StatsInnerTab_MouseLeftButtonUp(object sender, MouseButtonEventArgs e)
+    {
+        if (sender is not Border border || border.Tag is not string tag)
+            return;
+
+        if (string.Equals(tag, _codeStatsInnerTab, StringComparison.OrdinalIgnoreCase))
+            return;
+
+        _codeStatsInnerTab = tag;
+        SetCodeStatsInnerTabVisuals();
+        ApplyInnerTabVisibility();
+    }
+
+    private void ApplyInnerTabVisibility()
+    {
+        if (StatsOverviewPanel == null || StatsModelPanel == null || StatsHeatmapHost == null)
+            return;
+
+        var isOverview = string.Equals(_codeStatsInnerTab, "overview", StringComparison.OrdinalIgnoreCase);
+        StatsOverviewPanel.Visibility = isOverview ? Visibility.Visible : Visibility.Collapsed;
+        StatsHeatmapHost.Visibility = isOverview ? Visibility.Visible : Visibility.Collapsed;
+        StatsModelPanel.Visibility = isOverview ? Visibility.Collapsed : Visibility.Visible;
+    }
+
+    private void SetCodeStatsInnerTabVisuals()
+    {
+        var activeBackground = TryFindResource("ItemHoverBackground") as Brush ?? Brushes.Transparent;
+        var activeForeground = TryFindResource("PrimaryText") as Brush ?? Brushes.White;
+        var inactiveForeground = TryFindResource("SecondaryText") as Brush ?? Brushes.Gray;
+        var isOverview = string.Equals(_codeStatsInnerTab, "overview", StringComparison.OrdinalIgnoreCase);
+
+        if (StatsTabOverview != null)
+            StatsTabOverview.Background = isOverview ? activeBackground : Brushes.Transparent;
+        if (StatsTabOverviewLabel != null)
+        {
+            StatsTabOverviewLabel.Foreground = isOverview ? activeForeground : inactiveForeground;
+            StatsTabOverviewLabel.FontWeight = isOverview ? FontWeights.SemiBold : FontWeights.Normal;
+        }
+
+        if (StatsTabModel != null)
+            StatsTabModel.Background = isOverview ? Brushes.Transparent : activeBackground;
+        if (StatsTabModelLabel != null)
+        {
+            StatsTabModelLabel.Foreground = isOverview ? inactiveForeground : activeForeground;
+            StatsTabModelLabel.FontWeight = isOverview ? FontWeights.Normal : FontWeights.SemiBold;
+        }
+    }
+
+    private void StatsRange_MouseLeftButtonUp(object sender, MouseButtonEventArgs e)
+    {
+        if (sender is not Border border || border.Tag is not string tag)
+            return;
+
+        var newPeriod = tag switch
+        {
+            "all" => CodeStatsPeriod.All,
+            "7" => CodeStatsPeriod.Last7Days,
+            _ => CodeStatsPeriod.Last30Days,
+        };
+
+        if (newPeriod == _codeStatsPeriod)
+            return;
+
+        _codeStatsPeriod = newPeriod;
+        SetCodeStatsRangeVisuals();
+        _ = RefreshCodeStatsAsync();
+    }
+
+    private void SetCodeStatsRangeVisuals()
+    {
+        var activeBackground = TryFindResource("ItemHoverBackground") as Brush ?? Brushes.Transparent;
+        var activeForeground = TryFindResource("PrimaryText") as Brush ?? Brushes.White;
+        var inactiveForeground = TryFindResource("SecondaryText") as Brush ?? Brushes.Gray;
+
+        void Apply(Border? border, TextBlock? label, bool active)
+        {
+            if (border != null)
+                border.Background = active ? activeBackground : Brushes.Transparent;
+
+            if (label == null)
+                return;
+
+            label.Foreground = active ? activeForeground : inactiveForeground;
+            label.FontWeight = active ? FontWeights.SemiBold : FontWeights.Normal;
+        }
+
+        Apply(StatsRangeAll, StatsRangeAllLabel, _codeStatsPeriod == CodeStatsPeriod.All);
+        Apply(StatsRange30, StatsRange30Label, _codeStatsPeriod == CodeStatsPeriod.Last30Days);
+        Apply(StatsRange7, StatsRange7Label, _codeStatsPeriod == CodeStatsPeriod.Last7Days);
+    }
+
+    private static string FormatTokens(long count) => count switch
+    {
+        >= 1_000_000_000 => $"{count / 1_000_000_000.0:0.#}B",
+        >= 1_000_000 => $"{count / 1_000_000.0:0.#}M",
+        >= 1_000 => $"{count / 1_000.0:0.#}K",
+        _ => count.ToString("N0"),
+    };
+
+    private static string FormatNumber(int count) => count.ToString("N0");
+
+    private static string FormatHour(int? hour)
+    {
+        if (!hour.HasValue)
+            return "없음";
+
+        var value = hour.Value;
+        if (value == 0)
+            return "오전 12시";
+        if (value < 12)
+            return $"오전 {value}시";
+        if (value == 12)
+            return "오후 12시";
+        return $"오후 {value - 12}시";
+    }
+
+    private static string FormatModelName(string? raw)
+        => string.IsNullOrWhiteSpace(raw) ? "없음" : ShortenModelName(raw);
+
+    private static string ShortenModelName(string raw)
+    {
+        var separatorIndex = raw.IndexOf(':');
+        return separatorIndex > 0 && separatorIndex < raw.Length - 1
+            ? raw[(separatorIndex + 1)..]
+            : raw;
+    }
+}

src/AxCopilot/Views/ChatWindow.ConversationManagementPresentation.cs

@@ -397,11 +397,11 @@ public partial class ChatWindow
 
         stack.Children.Add(CreateSeparator());
 
-        // 아카이브 토글
+        // Archive toggle.
         var isArchived = _storage.Load(conversationId)?.Archived ?? false;
         stack.Children.Add(CreateMenuItem(
             isArchived ? "\uE7B8" : "\uE7B7",
-            isArchived ? "아카이브 해제" : "아카이브 보관",
+            isArchived ? "Unarchive" : "Archive",
             TryFindResource("SecondaryText") as Brush ?? Brushes.Gray, () =>
             {
                 var convToArchive = _storage.Load(conversationId);
@@ -416,9 +416,9 @@ public partial class ChatWindow
                 RefreshConversationList();
             }));
 
-        stack.Children.Add(CreateMenuItem("\uE74D", "이 대화 삭제", Brushes.IndianRed, () =>
+        stack.Children.Add(CreateMenuItem("\uE74D", "Delete conversation", Brushes.IndianRed, () =>
         {
-            var result = CustomMessageBox.Show("이 대화를 삭제하시겠습니까?", "대화 삭제",
+            var result = CustomMessageBox.Show("Delete this conversation?", "Delete conversation",
                 MessageBoxButton.YesNo, MessageBoxImage.Question);
             if (result != MessageBoxResult.Yes) return;
 
@@ -428,8 +428,9 @@ public partial class ChatWindow
                 if (_currentConversation?.Id == conversationId)
                 {
                     _currentConversation = null;
-        ClearTranscriptElements();
+                    ClearTranscriptElements();
                     EmptyState.Visibility = Visibility.Visible;
+                    UpdateCodeStatsVisibility();
                     UpdateChatTitle();
                 }
             }

src/AxCopilot/Views/ChatWindow.OverlaySettingsPresentation.cs

@@ -3820,6 +3820,7 @@ public partial class ChatWindow
         }
         ClearTranscriptElements();
         EmptyState.Visibility = Visibility.Visible;
+        UpdateCodeStatsVisibility();
         UpdateChatTitle();
         RefreshConversationList();
     }

src/AxCopilot/Views/ChatWindow.TopicPresetPresentation.cs

@@ -88,8 +88,9 @@ public partial class ChatWindow
                 SelectTopic(tag.Preset);
                 break;
             case "etc":
-                Services.LogService.Info($"[EmptyState] HIDE ← TopicButton_etc, tab={_activeTab}");
+                Services.LogService.Info($"[EmptyState] HIDE caller=TopicButton_etc, tab={_activeTab}");
                 EmptyState.Visibility = Visibility.Collapsed;
+                UpdateCodeStatsVisibility();
                 InputBox.Focus();
                 break;
             case "add":
@@ -123,18 +124,18 @@ public partial class ChatWindow
         if (_activeTab == "Cowork" || _activeTab == "Code")
         {
             if (EmptyStateTitle != null)
-                EmptyStateTitle.Text = _activeTab == "Code" ? "코드 작업을 입력하세요" : "작업 유형을 선택하세요";
+                EmptyStateTitle.Text = _activeTab == "Code" ? "Describe the coding task" : "Choose the work style";
             if (EmptyStateDesc != null)
                 EmptyStateDesc.Text = _activeTab == "Code"
-                    ? "코딩 에이전트가 코드 분석, 수정, 빌드, 테스트를 수행합니다"
+                    ? "The coding agent can inspect, modify, build, and test the workspace."
-                    : "에이전트가 상세한 데이터를 작성합니다";
+                    : "The agent can draft a detailed deliverable for the selected work style.";
         }
         else
         {
             if (EmptyStateTitle != null)
-                EmptyStateTitle.Text = "대화 주제를 선택하세요";
+                EmptyStateTitle.Text = "Choose a topic";
             if (EmptyStateDesc != null)
-                EmptyStateDesc.Text = "주제에 맞는 전문 프리셋이 자동 적용됩니다";
+                EmptyStateDesc.Text = "A matching prompt preset is applied automatically for the topic you choose.";
         }
 
         if (_activeTab == "Code")
@@ -603,13 +604,14 @@ public partial class ChatWindow
             _ = System.Threading.Tasks.Task.Run(() =>
             {
                 try { _storage.Save(convCopy); }
-                catch (Exception ex) { Services.LogService.Debug($"프리셋 저장 실패: {ex.Message}"); }
+                catch (Exception ex) { Services.LogService.Debug($"[Preset] save failed: {ex.Message}"); }
             });
         }
         if (EmptyState != null)
         {
-            Services.LogService.Info($"[EmptyState] HIDE ← SelectTopic, tab={_activeTab}");
+            Services.LogService.Info($"[EmptyState] HIDE caller=SelectTopic, tab={_activeTab}");
             EmptyState.Visibility = Visibility.Collapsed;
+            UpdateCodeStatsVisibility();
         }
 
         InputBox.Focus();

src/AxCopilot/Views/ChatWindow.TranscriptRendering.cs

@@ -8,10 +8,10 @@ namespace AxCopilot.Views;
 
 public partial class ChatWindow
 {
-    // ─── 렌더링 쓰로틀: 스트리밍 중 최소 간격 보장 ───────────────────────
+    // Render throttling keeps the transcript responsive during heavy streaming.
     private long _lastRenderTicks;
-    private const long MinStreamingRenderIntervalMs = 1500; // 스트리밍 중 최소 1.5초 간격
+    private const long MinStreamingRenderIntervalMs = 1500;
-    private const long MinIdleRenderIntervalMs = 300; // 비스트리밍(유휴) 시 최소 300ms 간격
+    private const long MinIdleRenderIntervalMs = 300;
 
     private int GetActiveTimelineRenderLimit()
     {
@@ -26,42 +26,38 @@ public partial class ChatWindow
 
     private void RenderMessages(bool preserveViewport = false, [System.Runtime.CompilerServices.CallerMemberName] string? caller = null)
     {
-        // B-4: 비가시 상태일 때 렌더링 차단 — 최소화/숨김 시 불필요한 UI 재구축 방지
+        // Skip background rendering when the window is not actually visible.
-        if (this.WindowState == System.Windows.WindowState.Minimized || !IsVisible)
+        if (WindowState == System.Windows.WindowState.Minimized || !IsVisible)
             return;
 
         var now = Environment.TickCount64;
 
-        // B-5: 스트리밍 중 쓰로틀 — preserveViewport=true (타이머 기반) 호출만 제한
+        // Throttle preserveViewport renders while streaming.
-        // preserveViewport=false는 사용자 메시지 전송 등 중요 렌더이므로 항상 허용
+        if (_isStreaming && preserveViewport && now - _lastRenderTicks < MinStreamingRenderIntervalMs)
-        if (_isStreaming && preserveViewport)
+            return;
-        {
-            if (now - _lastRenderTicks < MinStreamingRenderIntervalMs)
-                return;
-        }
 
-        // B-7: 유휴 상태 렌더 쓰로틀 — 빈 대화에서 반복 호출 방지 (UI 프리징 원인)
+        // Suppress rapid idle re-renders when the visible content is unchanged.
-        // 대화 내용이 바뀌지 않았는데 짧은 간격으로 반복 호출되면 무시
         if (!_isStreaming && now - _lastRenderTicks < MinIdleRenderIntervalMs)
         {
-            ChatConversation? quickConv;
+            ChatConversation? quickConversation;
-            lock (_convLock) quickConv = _currentConversation;
+            lock (_convLock)
-            var quickMsgCount = quickConv?.Messages?.Count ?? 0;
+                quickConversation = _currentConversation;
-            var quickEvtCount = quickConv?.ExecutionEvents?.Count ?? 0;
+
-            // 대화 내용이 마지막 렌더와 같으면 스킵 (빈 대화 반복 렌더 차단)
+            var quickMessageCount = quickConversation?.Messages?.Count ?? 0;
-            if (quickMsgCount == _lastRenderedMessageCount
+            var quickEventCount = quickConversation?.ExecutionEvents?.Count ?? 0;
-                && quickEvtCount == _lastRenderedEventCount
+
-                && string.Equals(_lastRenderedConversationId, quickConv?.Id, StringComparison.OrdinalIgnoreCase))
+            if (quickMessageCount == _lastRenderedMessageCount
+                && quickEventCount == _lastRenderedEventCount
+                && string.Equals(_lastRenderedConversationId, quickConversation?.Id, StringComparison.OrdinalIgnoreCase))
             {
                 return;
             }
-            // B-7b: 빈 대화 간 convId 플래핑 방지 — 둘 다 메시지 0개면
+
-            // convId가 달라도 빈 화면 렌더를 반복할 이유 없음 (SwitchToTabConversation 스팸 차단)
-            // 단, preserveViewport=false(탭 전환 등 명시적 렌더)는 차단하지 않음
-            // — 탭 전환 시 EmptyState/마스코트 표시에 필요
             if (preserveViewport
-                && quickMsgCount == 0 && quickEvtCount == 0
+                && quickMessageCount == 0
-                && _lastRenderedMessageCount == 0 && _lastRenderedEventCount == 0)
+                && quickEventCount == 0
+                && _lastRenderedMessageCount == 0
+                && _lastRenderedEventCount == 0)
             {
                 return;
             }
@@ -71,32 +67,33 @@ public partial class ChatWindow
         var previousScrollableHeight = GetTranscriptScrollableHeight();
         var previousVerticalOffset = GetTranscriptVerticalOffset();
 
-        ChatConversation? conv;
+        ChatConversation? conversation;
-        lock (_convLock) conv = _currentConversation;
+        lock (_convLock)
-        _appState.RestoreAgentRunHistory(conv?.AgentRunHistory);
+            conversation = _currentConversation;
 
-        var visibleMessages = GetVisibleTimelineMessages(conv);
+        _appState.RestoreAgentRunHistory(conversation?.AgentRunHistory);
-        var visibleEvents = GetVisibleTimelineEvents(conv);
 
-        // 진단 로그: 렌더링 호출 시점의 상태 추적
+        var visibleMessages = GetVisibleTimelineMessages(conversation);
-        Services.LogService.Info($"[Render] caller={caller}, preserveViewport={preserveViewport}, streaming={_isStreaming}, " +
+        var visibleEvents = GetVisibleTimelineEvents(conversation);
-            $"convId={conv?.Id?[..Math.Min(8, conv?.Id?.Length ?? 0)]}, " +
+
-            $"rawMsgCount={conv?.Messages?.Count ?? 0}, visibleMsg={visibleMessages.Count}, " +
+        LogService.Info($"[Render] caller={caller}, preserveViewport={preserveViewport}, streaming={_isStreaming}, " +
-            $"visibleEvt={visibleEvents.Count}, emptyState={EmptyState.Visibility}, " +
+                        $"convId={conversation?.Id?[..Math.Min(8, conversation?.Id?.Length ?? 0)]}, " +
-            $"transcriptElements={GetTranscriptElementCount()}");
+                        $"rawMsgCount={conversation?.Messages?.Count ?? 0}, visibleMsg={visibleMessages.Count}, " +
+                        $"visibleEvt={visibleEvents.Count}, emptyState={EmptyState.Visibility}, " +
+                        $"transcriptElements={GetTranscriptElementCount()}");
 
         if (_isStreaming && preserveViewport
             && visibleMessages.Count == _lastRenderedMessageCount
             && visibleEvents.Count == _lastRenderedEventCount
-            && (conv?.ShowExecutionHistory ?? true) == _lastRenderedShowHistory
+            && (conversation?.ShowExecutionHistory ?? true) == _lastRenderedShowHistory
-            && string.Equals(_lastRenderedConversationId, conv?.Id, StringComparison.OrdinalIgnoreCase))
+            && string.Equals(_lastRenderedConversationId, conversation?.Id, StringComparison.OrdinalIgnoreCase))
-            return;
-
-        if (conv == null || (visibleMessages.Count == 0 && visibleEvents.Count == 0))
         {
-            // 스트리밍 중이거나 대화에 원본 메시지가 있으면 EmptyState를 표시하지 않음
+            return;
-            // (GetVisibleTimelineMessages의 필터링으로 visibleMessages가 0이 되어도 원본은 존재)
+        }
-            bool hasRawMessages = (conv?.Messages?.Count ?? 0) > 0;
+
+        if (conversation == null || (visibleMessages.Count == 0 && visibleEvents.Count == 0))
+        {
+            var hasRawMessages = (conversation?.Messages?.Count ?? 0) > 0;
             if (!_isStreaming && !hasRawMessages)
             {
                 ClearTranscriptElements();
@@ -108,15 +105,15 @@ public partial class ChatWindow
             }
             else
             {
-                // 메시지가 있거나 스트리밍 중 → EmptyState 강제 숨김
                 HideEmptyState(animate: preserveViewport);
             }
+
             return;
         }
 
-        if (!string.Equals(_lastRenderedConversationId, conv.Id, StringComparison.OrdinalIgnoreCase))
+        if (!string.Equals(_lastRenderedConversationId, conversation.Id, StringComparison.OrdinalIgnoreCase))
         {
-            _lastRenderedConversationId = conv.Id;
+            _lastRenderedConversationId = conversation.Id;
             _timelineRenderLimit = TimelineRenderPageSize;
             _elementCache.Clear();
             _lastRenderedTimelineKeys.Clear();
@@ -127,41 +124,54 @@ public partial class ChatWindow
 
         HideEmptyState(animate: preserveViewport);
 
-        // V2 렌더링 (Claude Code 스타일 상세 이력 UI)
+        RenderMessagesV2(
-        RenderMessagesV2(conv, visibleMessages, visibleEvents, preserveViewport,
+            conversation,
-            previousScrollableHeight, previousVerticalOffset, renderStopwatch, caller);
+            visibleMessages,
+            visibleEvents,
+            preserveViewport,
+            previousScrollableHeight,
+            previousVerticalOffset,
+            renderStopwatch,
+            caller);
 
-        // 렌더 완료 후 진단 — transcript에 실제로 요소가 추가되었는지 확인
         var postRenderCount = GetTranscriptElementCount();
         if (postRenderCount == 0 && visibleMessages.Count > 0)
-            Services.LogService.Warn($"[Render] POST-RENDER WARNING: transcript has 0 elements after rendering {visibleMessages.Count} messages! caller={caller}, convId={conv?.Id?[..Math.Min(8, conv?.Id?.Length ?? 0)]}");
+        {
+            LogService.Warn($"[Render] POST-RENDER WARNING: transcript has 0 elements after rendering {visibleMessages.Count} messages! " +
+                            $"caller={caller}, convId={conversation?.Id?[..Math.Min(8, conversation?.Id?.Length ?? 0)]}");
+        }
     }
 
-    /// <summary>EmptyState를 표시합니다. 진행 중인 페이드 애니메이션을 취소하고 Opacity를 복원합니다.</summary>
+    /// <summary>
+    /// Shows EmptyState and cancels any in-flight fade animation.
+    /// </summary>
     private void ShowEmptyState([System.Runtime.CompilerServices.CallerMemberName] string? caller = null)
     {
-        var prev = EmptyState.Visibility;
+        var previousVisibility = EmptyState.Visibility;
         ++_emptyStateAnimationToken;
         EmptyState.BeginAnimation(OpacityProperty, null);
         EmptyState.Opacity = 1;
         EmptyState.Visibility = System.Windows.Visibility.Visible;
-        Services.LogService.Info($"[EmptyState] SHOW ← {caller}, prev={prev}, opacity={EmptyState.Opacity}, tab={_activeTab}");
+        UpdateCodeStatsVisibility();
+        LogService.Info($"[EmptyState] SHOW caller={caller}, prev={previousVisibility}, opacity={EmptyState.Opacity}, tab={_activeTab}");
         StartMascotAnimation();
     }
 
     /// <summary>
-    /// EmptyState를 숨깁니다. animate=true이면 150ms 페이드아웃, false이면 즉시 Collapsed.
+    /// Hides EmptyState. When animate is true, a 150 ms fade-out is used.
-    /// 토큰 기반 무효화: 탭 전환이나 ShowEmptyState가 호출되면 진행 중인 Completed 콜백이 무시됩니다.
+    /// Token-based invalidation prevents stale callbacks from collapsing a newly
+    /// shown EmptyState.
     /// </summary>
     private void HideEmptyState(bool animate, [System.Runtime.CompilerServices.CallerMemberName] string? caller = null)
     {
         if (EmptyState.Visibility != System.Windows.Visibility.Visible)
         {
             StopMascotAnimation();
+            UpdateCodeStatsVisibility();
             return;
         }
 
-        Services.LogService.Info($"[EmptyState] HIDE ← {caller}, animate={animate}, tab={_activeTab}");
+        LogService.Info($"[EmptyState] HIDE caller={caller}, animate={animate}, tab={_activeTab}");
 
         if (animate)
         {
@@ -170,17 +180,21 @@ public partial class ChatWindow
             {
                 EasingFunction = new System.Windows.Media.Animation.QuadraticEase()
             };
+
             fadeOut.Completed += (_, _) =>
             {
                 if (token != _emptyStateAnimationToken)
                 {
-                    Services.LogService.Info($"[EmptyState] HIDE animation STALE (token {token} vs {_emptyStateAnimationToken}), tab={_activeTab}");
+                    LogService.Info($"[EmptyState] HIDE animation stale (token {token} vs {_emptyStateAnimationToken}), tab={_activeTab}");
                     return;
                 }
+
                 EmptyState.Visibility = System.Windows.Visibility.Collapsed;
                 EmptyState.Opacity = 1;
-                Services.LogService.Info($"[EmptyState] HIDE animation COMPLETED, tab={_activeTab}");
+                UpdateCodeStatsVisibility();
+                LogService.Info($"[EmptyState] HIDE animation completed, tab={_activeTab}");
             };
+
             EmptyState.BeginAnimation(OpacityProperty, fadeOut);
         }
         else
@@ -189,7 +203,9 @@ public partial class ChatWindow
             EmptyState.BeginAnimation(OpacityProperty, null);
             EmptyState.Opacity = 1;
             EmptyState.Visibility = System.Windows.Visibility.Collapsed;
+            UpdateCodeStatsVisibility();
         }
+
         StopMascotAnimation();
     }
 }

src/AxCopilot/Views/ChatWindow.xaml

@@ -1848,7 +1848,8 @@
                         </Image>
                     </Canvas>
 
-                    <StackPanel HorizontalAlignment="Center"
+                    <StackPanel x:Name="EmptyStateCenterStack"
+                                HorizontalAlignment="Center"
                                 VerticalAlignment="Center"
                                 Margin="0,8,0,8">
                         <StackPanel HorizontalAlignment="Center"
@@ -1878,12 +1879,124 @@
                                       MaxHeight="420"
                                       Margin="0"
                                       Padding="0,4,0,8">
-                            <!-- 대화 주제 버튼 (프리셋에서 동적 생성) -->
+                            <!-- Topic preset buttons (dynamically populated). -->
                             <WrapPanel x:Name="TopicButtonPanel" HorizontalAlignment="Center"
                                        Margin="0,0,0,8"
                                        Background="Transparent"/>
                         </ScrollViewer>
                     </StackPanel>
+
+                    <!-- Code tab usage dashboard. -->
+                    <ScrollViewer x:Name="CodeStatsDashboardScroll"
+                                  Visibility="Collapsed"
+                                  VerticalScrollBarVisibility="Auto"
+                                  HorizontalScrollBarVisibility="Disabled"
+                                  Background="Transparent">
+                        <Grid x:Name="CodeStatsDashboard"
+                              HorizontalAlignment="Stretch"
+                              VerticalAlignment="Top"
+                              Margin="0,16,0,16">
+                            <Grid.RowDefinitions>
+                                <RowDefinition Height="Auto"/>
+                                <RowDefinition Height="Auto"/>
+                                <RowDefinition Height="Auto"/>
+                                <RowDefinition Height="Auto"/>
+                            </Grid.RowDefinitions>
+
+                            <Grid Grid.Row="0" Margin="0,0,0,14">
+                                <StackPanel Orientation="Horizontal" HorizontalAlignment="Left">
+                                    <Border x:Name="StatsTabOverview" Tag="overview"
+                                            Padding="12,6" Margin="0,0,6,0" CornerRadius="8"
+                                            Background="{DynamicResource ItemHoverBackground}"
+                                            BorderBrush="{DynamicResource BorderColor}" BorderThickness="1"
+                                            Cursor="Hand"
+                                            MouseLeftButtonUp="StatsInnerTab_MouseLeftButtonUp">
+                                        <TextBlock x:Name="StatsTabOverviewLabel" Text="개요"
+                                                   Foreground="{DynamicResource PrimaryText}"
+                                                   FontSize="12" FontWeight="SemiBold"/>
+                                    </Border>
+                                    <Border x:Name="StatsTabModel" Tag="model"
+                                            Padding="12,6" Margin="0,0,6,0" CornerRadius="8"
+                                            Background="Transparent"
+                                            BorderBrush="{DynamicResource BorderColor}" BorderThickness="1"
+                                            Cursor="Hand"
+                                            MouseLeftButtonUp="StatsInnerTab_MouseLeftButtonUp">
+                                        <TextBlock x:Name="StatsTabModelLabel" Text="모델"
+                                                   Foreground="{DynamicResource SecondaryText}"
+                                                   FontSize="12"/>
+                                    </Border>
+                                </StackPanel>
+                                <StackPanel Orientation="Horizontal" HorizontalAlignment="Right">
+                                    <Border x:Name="StatsRangeAll" Tag="all"
+                                            Padding="10,5" Margin="4,0,0,0" CornerRadius="6"
+                                            Background="Transparent"
+                                            BorderBrush="{DynamicResource BorderColor}" BorderThickness="1"
+                                            Cursor="Hand"
+                                            MouseLeftButtonUp="StatsRange_MouseLeftButtonUp">
+                                        <TextBlock x:Name="StatsRangeAllLabel" Text="전체"
+                                                   Foreground="{DynamicResource SecondaryText}" FontSize="11"/>
+                                    </Border>
+                                    <Border x:Name="StatsRange30" Tag="30"
+                                            Padding="10,5" Margin="4,0,0,0" CornerRadius="6"
+                                            Background="{DynamicResource ItemHoverBackground}"
+                                            BorderBrush="{DynamicResource BorderColor}" BorderThickness="1"
+                                            Cursor="Hand"
+                                            MouseLeftButtonUp="StatsRange_MouseLeftButtonUp">
+                                        <TextBlock x:Name="StatsRange30Label" Text="30일"
+                                                   Foreground="{DynamicResource PrimaryText}" FontSize="11"
+                                                   FontWeight="SemiBold"/>
+                                    </Border>
+                                    <Border x:Name="StatsRange7" Tag="7"
+                                            Padding="10,5" Margin="4,0,0,0" CornerRadius="6"
+                                            Background="Transparent"
+                                            BorderBrush="{DynamicResource BorderColor}" BorderThickness="1"
+                                            Cursor="Hand"
+                                            MouseLeftButtonUp="StatsRange_MouseLeftButtonUp">
+                                        <TextBlock x:Name="StatsRange7Label" Text="7일"
+                                                   Foreground="{DynamicResource SecondaryText}" FontSize="11"/>
+                                    </Border>
+                                </StackPanel>
+                            </Grid>
+
+                            <Grid x:Name="StatsOverviewPanel" Grid.Row="1">
+                                <UniformGrid x:Name="StatsCardGrid" Columns="4" Rows="2"/>
+                            </Grid>
+
+                            <StackPanel x:Name="StatsHeatmapHost" Grid.Row="2"
+                                        Margin="0,18,0,0" HorizontalAlignment="Stretch">
+                                <TextBlock Text="활동 히트맵 (최근 12주)"
+                                           FontSize="11" FontWeight="SemiBold"
+                                           Foreground="{DynamicResource SecondaryText}"
+                                           Margin="2,0,0,8"/>
+                                <Border CornerRadius="8" Padding="12"
+                                        Background="{DynamicResource ItemBackground}"
+                                        BorderBrush="{DynamicResource BorderColor}" BorderThickness="1">
+                                    <Canvas x:Name="StatsHeatmapCanvas" Height="124" HorizontalAlignment="Left"/>
+                                </Border>
+                                <TextBlock x:Name="StatsFooterFunFact" Margin="2,10,0,0"
+                                           FontSize="11" Foreground="{DynamicResource SecondaryText}"
+                                           Opacity="0.85"
+                                           Visibility="Collapsed"/>
+                            </StackPanel>
+
+                            <StackPanel x:Name="StatsModelPanel" Grid.Row="3"
+                                        Visibility="Collapsed" Margin="0,18,0,0">
+                                <TextBlock Text="모델별 일별 사용량"
+                                           FontSize="11" FontWeight="SemiBold"
+                                           Foreground="{DynamicResource SecondaryText}"
+                                           Margin="2,0,0,8"/>
+                                <Border CornerRadius="8" Padding="12,12,12,8"
+                                        Background="{DynamicResource ItemBackground}"
+                                        BorderBrush="{DynamicResource BorderColor}" BorderThickness="1">
+                                    <StackPanel>
+                                        <Canvas x:Name="StatsModelStackCanvas" Height="200"/>
+                                        <Canvas x:Name="StatsModelStackXAxis" Height="14" Margin="0,4,0,0"/>
+                                    </StackPanel>
+                                </Border>
+                                <ItemsControl x:Name="StatsModelLegend" Margin="2,12,0,0"/>
+                            </StackPanel>
+                        </Grid>
+                    </ScrollViewer>
                 </Grid>
 
                 <!-- ── 프롬프트 템플릿 팝업 ── -->

src/AxCopilot/Views/ChatWindow.xaml.cs

@@ -1461,6 +1461,7 @@ public partial class ChatWindow : Window
                 ? Visibility.Collapsed
                 : Visibility.Visible;
         }
+        UpdateCodeStatsVisibility();
         if (TopicButtonPanel != null)
             TopicButtonPanel.Visibility = Visibility.Visible;
     }
@@ -2047,6 +2048,7 @@ public partial class ChatWindow : Window
 
         // 현재 대화를 해당 탭 대화로 전환
         SwitchToTabConversation();
+        UpdateCodeStatsVisibility();
 
         // Cowork/Code 탭 전환 시 팁 표시
         ShowRandomTip();
@@ -4479,6 +4481,7 @@ public partial class ChatWindow : Window
         UpdateChatTitle();
         InputBox.Text = "";
         EmptyState.Visibility = Visibility.Collapsed;
+        UpdateCodeStatsVisibility();
         InvalidateTimelineCache();
         RenderMessages(preserveViewport: false);
 
@@ -4563,6 +4566,7 @@ public partial class ChatWindow : Window
         UpdateChatTitle();
         InputBox.Text = "";
         EmptyState.Visibility = Visibility.Collapsed;
+        UpdateCodeStatsVisibility();
         InvalidateTimelineCache();
         RenderMessages(preserveViewport: false);
     }
@@ -6010,6 +6014,7 @@ public partial class ChatWindow : Window
             UpdateInputBoxHeight();
         }
         EmptyState.Visibility = Visibility.Collapsed;
+        UpdateCodeStatsVisibility();
         StopMascotAnimation();
         InvalidateTimelineCache(); // 메시지 추가 직후 캐시 무효화 — 새 메시지 반영 보장
         try
@@ -6022,6 +6027,7 @@ public partial class ChatWindow : Window
         }
         // RenderMessages가 EmptyState를 Visible로 되돌릴 수 있으므로 강제 재설정
         EmptyState.Visibility = Visibility.Collapsed;
+        UpdateCodeStatsVisibility();
 
         // ── 디스크 I/O는 UI 갱신 후 비동기 실행 (UI 프리징 방지) ──
         var convForPersist = conv;