feat(ui): wire avalonia desktop ui to data and worker

App: build a ServiceProvider in Program.cs (AppSettings, SqliteConnectionFactory,
all repositories, GitService, WorkerClient, all view-models), apply schema, then
hand control to Avalonia. App.OnFrameworkInitializationCompleted resolves
MainWindowViewModel from the container.

Ui:
- AppSettings POCO loaded from ~/.todo-app/ui.config.json (db path, hub url).
- WorkerClient wraps HubConnection with auto-reconnect, exposes IsConnected and
  ActiveTasks plus C# events for TaskStarted/Finished/Message/Updated and
  WorktreeUpdated; all inbound events are marshalled to the UI thread.
- ViewModels: MainWindow (lists CRUD via ListEditor dialog), TaskList (load by
  list, add/edit/delete, auto WakeQueue on agent+queued create), TaskItem
  (RunNow gated on connection + status), TaskDetail (description, result, live
  ndjson rolling buffer of 500 lines, worktree branch/diff with merge/keep/
  discard via GitService), StatusBar, ListEditor, TaskEditor.
- Views: 3-pane MainWindow (lists | tasks | detail) with GridSplitters, status
  bar, dialog windows for the editors. Status badges via StatusColorConverter.
- Markdown rendering, folder picker, delete-confirmation, settings dialog and
  scroll-to-bottom on the live log are intentionally TODO -- functional
  scaffold only.

Tests: also debounce the FIFO queue test (poll instead of Task.Delay(200)) so
the assertion isn't racy when the suite runs alongside the slower git tests.
38 tests pass.

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

src/ClaudeDo.Ui/ViewModels/TaskItemViewModel.cs

@@ -0,0 +1,61 @@
+using ClaudeDo.Data.Models;
+using CommunityToolkit.Mvvm.ComponentModel;
+using CommunityToolkit.Mvvm.Input;
+using TaskStatus = ClaudeDo.Data.Models.TaskStatus;
+
+namespace ClaudeDo.Ui.ViewModels;
+
+public partial class TaskItemViewModel : ViewModelBase
+{
+    [ObservableProperty] private string _title;
+    [ObservableProperty] private string _statusText;
+    [ObservableProperty] private string _tagsText;
+    [ObservableProperty] private string _commitType;
+    [ObservableProperty] private string? _description;
+    [ObservableProperty] private TaskStatus _status;
+
+    public string Id { get; }
+    public string ListId { get; }
+    public TaskEntity Entity { get; private set; }
+
+    private readonly Func<string, Task>? _runNow;
+    private readonly Func<bool> _canRunNow;
+
+    public TaskItemViewModel(TaskEntity entity, IReadOnlyList<TagEntity> tags,
+        Func<string, Task>? runNow, Func<bool> canRunNow)
+    {
+        Entity = entity;
+        Id = entity.Id;
+        ListId = entity.ListId;
+        _title = entity.Title;
+        _status = entity.Status;
+        _statusText = entity.Status.ToString().ToLowerInvariant();
+        _tagsText = string.Join(", ", tags.Select(t => t.Name));
+        _commitType = entity.CommitType;
+        _description = entity.Description;
+        _runNow = runNow;
+        _canRunNow = canRunNow;
+    }
+
+    public void Refresh(TaskEntity entity, IReadOnlyList<TagEntity> tags)
+    {
+        Entity = entity;
+        Title = entity.Title;
+        Status = entity.Status;
+        StatusText = entity.Status.ToString().ToLowerInvariant();
+        TagsText = string.Join(", ", tags.Select(t => t.Name));
+        CommitType = entity.CommitType;
+        Description = entity.Description;
+        RunNowCommand.NotifyCanExecuteChanged();
+    }
+
+    [RelayCommand(CanExecute = nameof(CanRunNow))]
+    private async Task RunNowAsync()
+    {
+        if (_runNow is not null)
+            await _runNow(Id);
+    }
+
+    private bool CanRunNow() =>
+        _canRunNow() && Status == TaskStatus.Queued;
+}