feat(ui): add reconcile tick to self-heal lost worker broadcasts

TasksIslandViewModel now runs a periodic tick that diffs the flat Items
collection against SQLite and patches properties in place (capped at 500
rows, sharing the Phase 1 delta sequence guard so it never overtakes a
fresher broadcast). Never rebuilds rows or triggers Regroup/LoadForList, so
it stays decoupled from the parallel Phase 2b virtualization work. The same
cadence now refreshes the long-lived Worktrees Overview, Log Visualizer, and
Merge Helper selection overlays; short-lived modals are untouched.

src/ClaudeDo.Ui/ViewModels/Modals/LogVisualizerViewModel.cs

@@ -41,8 +41,16 @@ public sealed partial class LogVisualizerViewModel : ViewModelBase
         _worker = worker;
         _copyToClipboard = copyToClipboard;
         Rows.CollectionChanged += (_, _) => CopyLastCommand.NotifyCanExecuteChanged();
+        // Phase 3 reconcile tick: this overlay is long-lived (stays open while the user reads
+        // through the log), so refresh it on the same cadence as TasksIslandViewModel's tick
+        // instead of leaving it frozen at the moment it was opened.
+        _reconcileTimer.Elapsed += (_, _) =>
+            Avalonia.Threading.Dispatcher.UIThread.Post(() => _ = RefreshAsync());
+        _reconcileTimer.Start();
     }
 
+    private readonly System.Timers.Timer _reconcileTimer = new(4_000);
+
     [RelayCommand]
     public async Task RefreshAsync()
     {
@@ -65,7 +73,13 @@ public sealed partial class LogVisualizerViewModel : ViewModelBase
             : Loc.T("modals.logVisualizer.count", Rows.Count);
     }
 
-    [RelayCommand] private void Close() => CloseAction?.Invoke();
+    [RelayCommand]
+    private void Close()
+    {
+        _reconcileTimer.Stop();
+        _reconcileTimer.Dispose();
+        CloseAction?.Invoke();
+    }
 
     private bool CanCopyLast() => Rows.Count > 0;