fix: resolve critical bugs and improve reliability across worker, data, UI

- Fix worker using wrong DB by defaulting to CurrentUser service account
  and expanding ~ to absolute paths at install time
- Fix DbContext disposed before fire-and-forget by passing taskId instead
  of TaskEntity into RunInSlotAsync, which creates its own context
- Fix ActiveTaskDto property casing mismatch between hub and client
- Move WAL mode PRAGMA before migrations to prevent concurrent lock issues
- Replace FirstAsync with FirstOrDefaultAsync + null guards in tag operations
- Add delete confirmation flow for lists
- Log fire-and-forget exceptions instead of swallowing them
- Broadcast RunCreated event from WorkerHub.RunNow
- Add IDisposable to MainWindowViewModel for event handler cleanup
- Preserve subtask CreatedAt on updates instead of overwriting
- Replace bare catch blocks with Debug.WriteLine logging

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

src/ClaudeDo.Ui/ViewModels/MainWindowViewModel.cs

@@ -13,7 +13,7 @@ using Microsoft.EntityFrameworkCore;
 
 namespace ClaudeDo.Ui.ViewModels;
 
-public partial class MainWindowViewModel : ViewModelBase
+public partial class MainWindowViewModel : ViewModelBase, IDisposable
 {
     private readonly IDbContextFactory<ClaudeDoDbContext> _dbFactory;
     private readonly WorkerClient _worker;
@@ -27,6 +27,8 @@ public partial class MainWindowViewModel : ViewModelBase
     public TaskDetailViewModel TaskDetail { get; }
     public StatusBarViewModel StatusBar { get; }
 
+    private readonly Action<string> _onTaskChanged;
+
     public MainWindowViewModel(
         IDbContextFactory<ClaudeDoDbContext> dbFactory,
         WorkerClient worker,
@@ -42,8 +44,15 @@ public partial class MainWindowViewModel : ViewModelBase
         TaskDetail = taskDetail;
         StatusBar = statusBar;
 
+        _onTaskChanged = taskId => _ = TaskList.RefreshSingleAsync(taskId);
         TaskList.SelectedTaskChanged += OnSelectedTaskChanged;
-        TaskDetail.TaskChanged += taskId => _ = TaskList.RefreshSingleAsync(taskId);
+        TaskDetail.TaskChanged += _onTaskChanged;
+    }
+
+    public void Dispose()
+    {
+        TaskList.SelectedTaskChanged -= OnSelectedTaskChanged;
+        TaskDetail.TaskChanged -= _onTaskChanged;
     }
 
     public async Task InitializeAsync()
@@ -61,7 +70,11 @@ public partial class MainWindowViewModel : ViewModelBase
             StatusBar.ShowMessage($"Error loading lists: {ex.Message}");
         }
 
-        _ = _worker.StartAsync();
+        _ = _worker.StartAsync().ContinueWith(t =>
+        {
+            if (t.IsFaulted)
+                System.Diagnostics.Debug.WriteLine($"Worker connection failed: {t.Exception?.Message}");
+        }, TaskScheduler.Default);
     }
 
     partial void OnSelectedListChanged(ListItemViewModel? value)
@@ -154,23 +167,46 @@ public partial class MainWindowViewModel : ViewModelBase
         }
     }
 
+    [ObservableProperty] private bool _isDeleteConfirmVisible;
+    private ListItemViewModel? _pendingDeleteList;
+
     [RelayCommand]
-    private async Task DeleteList()
+    private void DeleteList()
     {
         if (SelectedList is null) return;
-        // TODO: confirmation dialog
+        _pendingDeleteList = SelectedList;
+        IsDeleteConfirmVisible = true;
+    }
+
+    [RelayCommand]
+    private async Task ConfirmDeleteList()
+    {
+        IsDeleteConfirmVisible = false;
+        if (_pendingDeleteList is null) return;
         try
         {
             using var context = _dbFactory.CreateDbContext();
             var listRepo = new ListRepository(context);
-            await listRepo.DeleteAsync(SelectedList.Id);
-            Lists.Remove(SelectedList);
-            SelectedList = null;
+            await listRepo.DeleteAsync(_pendingDeleteList.Id);
+            Lists.Remove(_pendingDeleteList);
+            if (SelectedList == _pendingDeleteList)
+                SelectedList = null;
         }
         catch (Exception ex)
         {
             StatusBar.ShowMessage($"Error deleting list: {ex.Message}");
         }
+        finally
+        {
+            _pendingDeleteList = null;
+        }
+    }
+
+    [RelayCommand]
+    private void CancelDeleteList()
+    {
+        IsDeleteConfirmVisible = false;
+        _pendingDeleteList = null;
     }
 
     private static async Task ShowDialogAsync(Window dialog)

src/ClaudeDo.Ui/ViewModels/TaskDetailViewModel.cs

@@ -282,16 +282,18 @@ public partial class TaskDetailViewModel : ViewModelBase
         if (e.PropertyName is not (nameof(SubtaskItemViewModel.Title) or nameof(SubtaskItemViewModel.Completed))) return;
         try
         {
+            if (_taskId is null) return;
             using var context = _dbFactory.CreateDbContext();
+            var orig = await context.Subtasks.AsNoTracking().FirstOrDefaultAsync(s => s.Id == vm.Id);
             var subtaskRepo = new SubtaskRepository(context);
             await subtaskRepo.UpdateAsync(new SubtaskEntity
             {
                 Id = vm.Id,
-                TaskId = _taskId ?? "",
+                TaskId = _taskId,
                 Title = vm.Title,
                 Completed = vm.Completed,
                 OrderNum = Subtasks.IndexOf(vm),
-                CreatedAt = DateTime.UtcNow,
+                CreatedAt = orig?.CreatedAt ?? DateTime.UtcNow,
             });
         }
         catch (Exception ex)
@@ -378,13 +380,15 @@ public partial class TaskDetailViewModel : ViewModelBase
                 UseShellExecute = true,
             });
         }
-        catch { /* best effort */ }
+        catch (Exception ex)
+        {
+            Debug.WriteLine($"Failed to open worktree: {ex.Message}");
+        }
     }
 
     [RelayCommand]
     private void ShowDiff()
     {
-        // TODO: open a proper diff viewer; for now open git diff in a console
         if (WorktreePath is null) return;
         try
         {
@@ -395,7 +399,10 @@ public partial class TaskDetailViewModel : ViewModelBase
                 UseShellExecute = true,
             });
         }
-        catch { /* best effort */ }
+        catch (Exception ex)
+        {
+            Debug.WriteLine($"Failed to show diff: {ex.Message}");
+        }
     }
 
     [RelayCommand]

src/ClaudeDo.Ui/ViewModels/TaskEditorViewModel.cs

@@ -215,7 +215,10 @@ public partial class TaskEditorViewModel : ViewModelBase
             {
                 if (vm.Id == "") continue;
                 if (vm.Title != vm.OriginalTitle || vm.Completed != vm.OriginalCompleted)
-                    await subtaskRepo.UpdateAsync(new SubtaskEntity { Id = vm.Id, TaskId = taskId, Title = vm.Title, Completed = vm.Completed, OrderNum = idx, CreatedAt = DateTime.UtcNow });
+                {
+                    var origSub = existing.FirstOrDefault(e => e.Id == vm.Id);
+                    await subtaskRepo.UpdateAsync(new SubtaskEntity { Id = vm.Id, TaskId = taskId, Title = vm.Title, Completed = vm.Completed, OrderNum = idx, CreatedAt = origSub?.CreatedAt ?? DateTime.UtcNow });
+                }
                 else
                 {
                     // update order_num if position changed