fix(ui): toggle expand on full folder row click

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/ClaudeDo.Ui/Views/Modals/WorktreeModalView.axaml

@@ -59,6 +59,7 @@
           <TreeView.ItemTemplate>
             <TreeDataTemplate DataType="vm:WorktreeNodeViewModel"
                               ItemsSource="{Binding Children}">
+              <Border Background="Transparent" Tapped="OnNodeTapped" Cursor="Hand">
               <StackPanel Orientation="Horizontal" Spacing="8">
                 <TextBlock Text="{Binding Name}"
                            FontFamily="{DynamicResource MonoFont}" FontSize="12"
@@ -71,6 +72,7 @@
                              Foreground="{DynamicResource TextBrush}"/>
                 </Border>
               </StackPanel>
+              </Border>
             </TreeDataTemplate>
           </TreeView.ItemTemplate>
         </TreeView>

src/ClaudeDo.Ui/Views/Modals/WorktreeModalView.axaml.cs

@@ -5,6 +5,7 @@ using Avalonia.Controls;
 using Avalonia.Input;
 using Avalonia.Media;
 using Avalonia.Styling;
+using Avalonia.VisualTree;
 using ClaudeDo.Ui.ViewModels.Modals;
 
 namespace ClaudeDo.Ui.Views.Modals;
@@ -56,6 +57,16 @@ public partial class WorktreeModalView : Window
         RenderTransform = new ScaleTransform(1.0, 1.0);
     }
 
+    private void OnNodeTapped(object? sender, Avalonia.Input.TappedEventArgs e)
+    {
+        if (sender is not Control c) return;
+        if (c.DataContext is not WorktreeNodeViewModel node) return;
+        if (!node.IsDirectory) return;
+        var tvi = c.FindAncestorOfType<TreeViewItem>();
+        if (tvi is null) return;
+        tvi.IsExpanded = !tvi.IsExpanded;
+    }
+
     private void OnTitleBarPressed(object? sender, PointerPressedEventArgs e)
     {
         if (e.GetCurrentPoint(this).Properties.IsLeftButtonPressed)