fix(ui): wire delete confirm, close-details, uppercase eyebrow, explorer button

- A1: list-name eyebrow runs through UpperCase converter.
- D2: + Open-in-explorer icon button in AgentStrip (Process.Start on worktree path).
- D4: DeleteTaskCommand prompts inline confirm Window before deleting; shell
  wires Details.CloseDetail to clear Tasks.SelectedTask and Details.DeleteFromList
  to reload the current list.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/ClaudeDo.Ui/ViewModels/Islands/DetailsIslandViewModel.cs

@@ -78,6 +78,9 @@ public sealed partial class DetailsIslandViewModel : ViewModelBase
     // Set by the view so OpenWorktreeCommand can show the modal as a dialog
     public Func<WorktreeModalViewModel, System.Threading.Tasks.Task>? ShowWorktreeModal { get; set; }
 
+    // Set by the view so DeleteTaskCommand can prompt yes/no before deleting
+    public Func<string, System.Threading.Tasks.Task<bool>>? ConfirmAsync { get; set; }
+
     public DetailsIslandViewModel(IDbContextFactory<ClaudeDoDbContext> dbFactory, WorkerClient worker, IServiceProvider services)
     {
         _dbFactory = dbFactory;
@@ -186,10 +189,26 @@ public sealed partial class DetailsIslandViewModel : ViewModelBase
 
     private bool CanOpenWorktree() => WorktreePath != null;
 
+    [RelayCommand(CanExecute = nameof(CanOpenWorktree))]
+    private void OpenInExplorer()
+    {
+        if (WorktreePath == null) return;
+        try
+        {
+            System.Diagnostics.Process.Start(new System.Diagnostics.ProcessStartInfo
+            {
+                FileName = WorktreePath,
+                UseShellExecute = true,
+            });
+        }
+        catch { /* explorer open is best-effort */ }
+    }
+
     partial void OnWorktreePathChanged(string? value)
     {
         OpenDiffCommand.NotifyCanExecuteChanged();
         OpenWorktreeCommand.NotifyCanExecuteChanged();
+        OpenInExplorerCommand.NotifyCanExecuteChanged();
     }
 
     [RelayCommand]
@@ -212,6 +231,11 @@ public sealed partial class DetailsIslandViewModel : ViewModelBase
     {
         if (Task == null) return;
         var row = Task;
+        if (ConfirmAsync != null)
+        {
+            var ok = await ConfirmAsync($"Delete \"{row.Title}\"? This cannot be undone.");
+            if (!ok) return;
+        }
         await using var ctx = _dbFactory.CreateDbContext();
         var repo = new TaskRepository(ctx);
         await repo.DeleteAsync(row.Id);