feat(daily-prep): trigger planning from inside the prep-log window with an empty-state hint

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

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

@@ -37,15 +37,6 @@ public sealed partial class TasksIslandViewModel : ViewModelBase
         NotesRequested?.Invoke();
     }
 
-    [RelayCommand]
-    private async Task PrepareDayAsync()
-    {
-        if (_worker is null) return;
-        PrepRequested?.Invoke();
-        try { await _worker.RunDailyPrepNowAsync(); }
-        catch { /* worker offline; broadcast will reconcile on return */ }
-    }
-
     [RelayCommand]
     private void ShowPrepLog() => PrepRequested?.Invoke();