슬래시 팝업 밀도 압축 2단계: 컴팩트 레이아웃/행 높이 조정

- ChatWindow.xaml에서 slash 팝업 폭/높이/헤더/리스트/푸터 패딩을 축소해 한 화면 정보량을 증가

- ChatWindow.xaml.cs에서 섹션 헤더/명령 항목의 폰트와 패딩을 낮춰 Codex형 컴팩트 탐색 밀도 반영

- 스크롤/선택 UX(재렌더링 최소화) 경로와 충돌 없이 시각 밀도만 조정

- README.md, docs/DEVELOPMENT.md에 2026-04-04 14:09(KST) 기준 이력 반영

- 검증: dotnet build 0경고/0오류, slash 관련 필터 테스트 41건 통과

src/AxCopilot/Views/ChatWindow.xaml.cs

@@ -5255,8 +5255,8 @@ public partial class ChatWindow : Window
                 BorderBrush = borderBrush,
                 BorderThickness = new Thickness(1),
                 CornerRadius = new CornerRadius(8),
-                Padding = new Thickness(10, 6, 10, 6),
-                Margin = new Thickness(0, 0, 0, 6),
+                Padding = new Thickness(9, 5, 9, 5),
+                Margin = new Thickness(0, 0, 0, 5),
                 Cursor = Cursors.Hand,
             };
             var grid = new Grid();
@@ -5276,7 +5276,7 @@ public partial class ChatWindow : Window
             var titleText = new TextBlock
             {
                 Text = $"{title} {count}",
-                FontSize = 10.5,
+                FontSize = 10,
                 FontWeight = FontWeights.SemiBold,
                 Foreground = primaryText,
                 VerticalAlignment = VerticalAlignment.Center,
@@ -5286,7 +5286,7 @@ public partial class ChatWindow : Window
             var metaText = new TextBlock
             {
                 Text = expanded ? "접기" : "펼치기",
-                FontSize = 10,
+                FontSize = 9.5,
                 Foreground = secondaryText,
                 VerticalAlignment = VerticalAlignment.Center,
             };
@@ -5328,8 +5328,8 @@ public partial class ChatWindow : Window
                 BorderBrush = borderBrush,
                 BorderThickness = new Thickness(1),
                 CornerRadius = new CornerRadius(10),
-                Padding = new Thickness(10, 7, 10, 7),
-                Margin = new Thickness(0, 0, 0, 4),
+                Padding = new Thickness(9, 6, 9, 6),
+                Margin = new Thickness(0, 0, 0, 3),
                 Cursor = skillAvailable ? Cursors.Hand : Cursors.Arrow,
                 Opacity = skillAvailable ? 1.0 : 0.5,
             };
@@ -5351,7 +5351,7 @@ public partial class ChatWindow : Window
             titleRow.Children.Add(new TextBlock
             {
                 Text = cmd,
-                FontSize = 13,
+                FontSize = 12.5,
                 FontWeight = FontWeights.SemiBold,
                 Foreground = skillAvailable ? primaryText : secondaryText,
                 VerticalAlignment = VerticalAlignment.Center,
@@ -5396,10 +5396,10 @@ public partial class ChatWindow : Window
             leftStack.Children.Add(new TextBlock
             {
                 Text = label,
-                FontSize = 11.5,
+                FontSize = 11,
                 Foreground = secondaryText,
                 VerticalAlignment = VerticalAlignment.Center,
-                Margin = new Thickness(18, 2, 0, 0),
+                Margin = new Thickness(18, 1.5, 0, 0),
                 TextTrimming = TextTrimming.CharacterEllipsis,
             });
             Grid.SetColumn(leftStack, 0);