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/Islands/ListsIslandViewModel.cs

@@ -16,7 +16,7 @@ namespace ClaudeDo.Ui.ViewModels.Islands;
 
 public enum ListKind { Smart, Virtual, User }
 
-public sealed partial class ListsIslandViewModel : ViewModelBase
+public sealed partial class ListsIslandViewModel : ViewModelBase, IDisposable
 {
     private readonly IDbContextFactory<ClaudeDoDbContext> _dbFactory;
     private readonly IServiceProvider? _services;
@@ -141,6 +141,8 @@ public sealed partial class ListsIslandViewModel : ViewModelBase
     public string MachineNameLocal => Loc.T("vm.lists.localSuffix", MachineName);
     public string UserInitials { get; }
 
+    private readonly EventHandler _langChangedHandler;
+
     public ListsIslandViewModel(IDbContextFactory<ClaudeDoDbContext> dbFactory, IServiceProvider? services = null, WorkerClient? worker = null)
     {
         _dbFactory = dbFactory;
@@ -163,7 +165,13 @@ public sealed partial class ListsIslandViewModel : ViewModelBase
             _worker.ConnectionRestoredEvent += ()                      => _ = RefreshCountsAsync();
         }
 
-        Loc.LanguageChanged += (_, _) => RefreshLocalizedLabels();
+        _langChangedHandler = (_, _) => RefreshLocalizedLabels();
+        Loc.LanguageChanged += _langChangedHandler;
+    }
+
+    public void Dispose()
+    {
+        Loc.LanguageChanged -= _langChangedHandler;
     }
 
     private static string? SmartListNameKey(string id) => id switch