fix(ui): dispose VM subscriptions/timers, guard offline Stop, align review delta-path

- DetailsIslandViewModel/TasksIslandViewModel/ListsIslandViewModel: implement
  IDisposable, unsubscribe Loc.LanguageChanged and worker events (memory leaks).
- IslandsShellViewModel: dispose the three System.Timers.Timer instances.
- StopAsync: guard on Task/IsRunning/IsConnected and wrap CancelTask in try/catch.
- TaskMatchesList virtual:review now matches WaitingForReview (aligns with ReviewFilter).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

src/ClaudeDo.Ui/ViewModels/IslandsShellViewModel.cs

@@ -15,7 +15,7 @@ using Microsoft.EntityFrameworkCore;
 
 namespace ClaudeDo.Ui.ViewModels;
 
-public sealed partial class IslandsShellViewModel : ViewModelBase
+public sealed partial class IslandsShellViewModel : ViewModelBase, IDisposable
 {
     public ListsIslandViewModel? Lists { get; }
     public TasksIslandViewModel? Tasks { get; }
@@ -268,6 +268,16 @@ public sealed partial class IslandsShellViewModel : ViewModelBase
         });
     }
 
+    public void Dispose()
+    {
+        _clearTimer.Stop();
+        _clearTimer.Dispose();
+        _connectTimer.Stop();
+        _connectTimer.Dispose();
+        _primeStatusTimer.Stop();
+        _primeStatusTimer.Dispose();
+    }
+
     private void RefreshBannerFromStatus()
     {
         switch (_updateCheck.LastCheckStatus)