fix(ui): fix live output visibility and editor dialog graying out

- Remove wrapping ScrollViewer from live output TextBox — Avalonia
  TextBox with AcceptsReturn handles its own scrolling; nested
  ScrollViewer caused layout collapse
- Auto-scroll via CaretIndex instead of removed ScrollViewer
- Add OnWindowClosed to both editor ViewModels, ensuring the
  TaskCompletionSource always resolves when the dialog closes
  (including via X button), preventing RelayCommand from staying
  permanently disabled

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

src/ClaudeDo.Ui/ViewModels/ListEditorViewModel.cs

@@ -114,6 +114,11 @@ public partial class ListEditorViewModel : ViewModelBase
         RequestClose?.Invoke();
     }
 
+    public void OnWindowClosed()
+    {
+        _tcs.TrySetResult(null);
+    }
+
     public Task<ListEntity?> ShowAndWaitAsync()
     {
         _tcs = new TaskCompletionSource<ListEntity?>();

src/ClaudeDo.Ui/ViewModels/MainWindowViewModel.cs

@@ -83,6 +83,7 @@ public partial class MainWindowViewModel : ViewModelBase
 
         var window = new ListEditorView { DataContext = editor };
         editor.RequestClose += () => window.Close();
+        window.Closed += (_, _) => editor.OnWindowClosed();
         _ = ShowDialogAsync(window);
 
         var entity = await editor.ShowAndWaitAsync();
@@ -116,6 +117,7 @@ public partial class MainWindowViewModel : ViewModelBase
 
         var window = new ListEditorView { DataContext = editor };
         editor.RequestClose += () => window.Close();
+        window.Closed += (_, _) => editor.OnWindowClosed();
         _ = ShowDialogAsync(window);
 
         var entity = await editor.ShowAndWaitAsync();

src/ClaudeDo.Ui/ViewModels/TaskEditorViewModel.cs

@@ -113,6 +113,11 @@ public partial class TaskEditorViewModel : ViewModelBase
         RequestClose?.Invoke();
     }
 
+    public void OnWindowClosed()
+    {
+        _tcs.TrySetResult(null);
+    }
+
     public Task<TaskEntity?> ShowAndWaitAsync()
     {
         _tcs = new TaskCompletionSource<TaskEntity?>();

src/ClaudeDo.Ui/ViewModels/TaskListViewModel.cs

@@ -151,6 +151,7 @@ public partial class TaskListViewModel : ViewModelBase
 
         var window = new TaskEditorView { DataContext = editor };
         editor.RequestClose += () => window.Close();
+        window.Closed += (_, _) => editor.OnWindowClosed();
         _ = ShowDialogAsync(window);
 
         var saved = await editor.ShowAndWaitAsync();
@@ -197,6 +198,7 @@ public partial class TaskListViewModel : ViewModelBase
 
         var window = new TaskEditorView { DataContext = editor };
         editor.RequestClose += () => window.Close();
+        window.Closed += (_, _) => editor.OnWindowClosed();
         _ = ShowDialogAsync(window);
 
         var saved = await editor.ShowAndWaitAsync();

src/ClaudeDo.Ui/Views/TaskDetailView.axaml

@@ -106,22 +106,19 @@
 
             <TextBlock Text="Live Output" FontWeight="SemiBold" FontSize="12"
                        Foreground="{StaticResource TextSecondaryBrush}" Margin="0,8,0,2"/>
-            <Border BorderBrush="{StaticResource BorderSubtleBrush}" BorderThickness="1"
-                    CornerRadius="6" Padding="6" MaxHeight="300">
-                <ScrollViewer x:Name="LiveOutputScroll">
-                    <TextBox x:Name="LiveOutputBox"
-                             Text="{Binding LiveText, Mode=OneWay}"
-                             IsReadOnly="True"
-                             AcceptsReturn="True"
-                             TextWrapping="NoWrap"
-                             FontFamily="Consolas,Courier New,monospace"
-                             FontSize="11"
-                             Foreground="{StaticResource TextPrimaryBrush}"
-                             Background="Transparent"
-                             BorderThickness="0"
-                             Padding="0"/>
-                </ScrollViewer>
-            </Border>
+            <TextBox x:Name="LiveOutputBox"
+                     Text="{Binding LiveText, Mode=OneWay}"
+                     IsReadOnly="True"
+                     AcceptsReturn="True"
+                     TextWrapping="NoWrap"
+                     FontFamily="Consolas,Courier New,monospace"
+                     FontSize="11"
+                     MaxHeight="300"
+                     Foreground="{StaticResource TextPrimaryBrush}"
+                     BorderBrush="{StaticResource BorderSubtleBrush}"
+                     BorderThickness="1"
+                     CornerRadius="6"
+                     Padding="6"/>
 
             <Border IsVisible="{Binding HasWorktree}" BorderBrush="{StaticResource AccentBrush}"
                     BorderThickness="1" CornerRadius="8" Padding="10" Margin="0,8,0,0">

src/ClaudeDo.Ui/Views/TaskDetailView.axaml.cs

@@ -49,8 +49,11 @@ public partial class TaskDetailView : UserControl
     {
         if (e.PropertyName == nameof(TaskDetailViewModel.LiveText))
         {
-            var scroll = this.FindControl<ScrollViewer>("LiveOutputScroll");
-            scroll?.ScrollToEnd();
+            var box = this.FindControl<TextBox>("LiveOutputBox");
+            if (box is not null)
+            {
+                box.CaretIndex = box.Text?.Length ?? 0;
+            }
         }
     }
 }