feat(ui): editable task status and tags from details panel

Adds a status ComboBox in the Details header (no transition guards)
and a Tags section with chips + AutoCompleteBox. TaskRowViewModel.Tags
becomes an ObservableCollection so chip lists stay live. TasksIsland
caches AllTags for the row context menu and exposes Set/Toggle helpers.
Test fakes updated for the new IWorkerClient methods.

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

src/ClaudeDo.Ui/Services/WorkerClient.cs

@@ -381,6 +381,28 @@ public partial class WorkerClient : ObservableObject, IAsyncDisposable, IWorkerC
         await _hub.InvokeAsync("UpdateTaskAgentSettings", dto);
     }
 
+    public async Task SetTaskStatusAsync(string taskId, ClaudeDo.Data.Models.TaskStatus status)
+    {
+        await _hub.InvokeAsync("SetTaskStatus", taskId, status.ToString());
+    }
+
+    public async Task SetTaskTagsAsync(string taskId, IEnumerable<string> tagNames)
+    {
+        await _hub.InvokeAsync("SetTaskTags", taskId, tagNames.ToArray());
+    }
+
+    public async Task<List<string>> GetAllTagsAsync()
+    {
+        try
+        {
+            return await _hub.InvokeAsync<List<string>>("GetAllTags") ?? new List<string>();
+        }
+        catch
+        {
+            return new List<string>();
+        }
+    }
+
     public async Task<WorktreeCleanupDto?> CleanupFinishedWorktreesAsync()
     {
         try