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

@@ -861,7 +861,7 @@
                     <Border Background="{DynamicResource LauncherBackground}"
                             BorderBrush="{DynamicResource BorderColor}"
                             BorderThickness="1" CornerRadius="18"
-                            Padding="0" MinWidth="620" MaxWidth="780"
+                            Padding="0" MinWidth="580" MaxWidth="740"
                             PreviewMouseWheel="SlashPopup_PreviewMouseWheel">
                         <Border.Effect>
                             <DropShadowEffect BlurRadius="16" ShadowDepth="0" Opacity="0.16"/>
@@ -871,7 +871,7 @@
                                     BorderBrush="{DynamicResource BorderColor}"
                                     BorderThickness="0,0,0,1"
                                     CornerRadius="18,18,0,0"
-                                    Padding="14,12,14,10">
+                                    Padding="12,10,12,8">
                                 <StackPanel>
                                     <Grid>
                                         <Grid.ColumnDefinitions>
@@ -882,7 +882,7 @@
                                         <StackPanel Orientation="Horizontal" Grid.Column="0">
                                             <Border Background="{DynamicResource AccentColor}"
                                                     CornerRadius="8"
-                                                    Padding="6,2"
+                                                    Padding="5,1.5"
                                                     Margin="0,0,8,0"
                                                     VerticalAlignment="Center">
                                                 <TextBlock Text="/"
@@ -892,7 +892,7 @@
                                             </Border>
                                             <TextBlock x:Name="SlashPopupTitle"
                                                        Text="명령 및 스킬"
-                                                       FontSize="13.5"
+                                                       FontSize="13"
                                                        FontWeight="SemiBold"
                                                        Foreground="{DynamicResource PrimaryText}"
                                                        VerticalAlignment="Center"/>
@@ -901,7 +901,7 @@
                                                 x:Name="BtnSlashReset"
                                                 Click="BtnSlashReset_Click"
                                                 Style="{StaticResource GhostBtn}"
-                                                Padding="8,4"
+                                                Padding="7,3"
                                                 Margin="0,0,6,0"
                                                 ToolTip="핀/최근 정리">
                                             <StackPanel Orientation="Horizontal">
@@ -919,7 +919,7 @@
                                                 x:Name="BtnSlashToggleGroups"
                                                 Click="BtnSlashToggleGroups_Click"
                                                 Style="{StaticResource GhostBtn}"
-                                                Padding="8,4"
+                                                Padding="7,3"
                                                 ToolTip="명령/스킬 그룹 전체 접기 또는 펼치기">
                                             <StackPanel Orientation="Horizontal">
                                                 <TextBlock Text="&#xE70D;"
@@ -936,25 +936,25 @@
                                     </Grid>
                                     <TextBlock x:Name="SlashPopupHint"
                                                Text="방향키나 마우스 휠로 이동하고 Enter로 바로 실행합니다"
-                                               FontSize="11.5"
+                                               FontSize="11"
                                                Foreground="{DynamicResource SecondaryText}"
-                                               Margin="0,6,0,0"/>
+                                               Margin="0,5,0,0"/>
                                 </StackPanel>
                             </Border>
                             <ScrollViewer x:Name="SlashScrollViewer"
-                                          MaxHeight="420"
+                                          MaxHeight="380"
                                           VerticalScrollBarVisibility="Auto"
                                           HorizontalScrollBarVisibility="Disabled"
                                           CanContentScroll="False"
                                           PanningMode="VerticalOnly"
                                           PreviewMouseWheel="SlashPopup_PreviewMouseWheel"
-                                          Padding="10,10,10,8">
+                                          Padding="8,8,8,6">
                                 <ItemsControl x:Name="SlashItems"/>
                             </ScrollViewer>
                             <TextBlock x:Name="SlashPopupFooter"
-                                       Margin="14,0,14,12"
+                                       Margin="12,0,12,10"
                                        Text="Enter 실행 · ↑↓ 이동 · 휠 스크롤 · Esc 닫기"
-                                       FontSize="10.5"
+                                       FontSize="10"
                                        Foreground="{DynamicResource SecondaryText}"/>
                         </StackPanel>
                     </Border>