feat(ui): remove a queued interactive message with a ✕

Queued rows are now QueuedMessageViewModel (Text + RemoveCommand); each shows a
✕ (Icon.WinClose) that calls RemoveQueuedInteractiveMessageAsync(taskId, text).
The worker re-broadcasts the queue, rebuilding the strip without the removed
message. Adds session.composer.unqueue (en/de).

src/ClaudeDo.Localization/locales/en.json

@@ -237,7 +237,8 @@
       "send": "Send",
       "stop": "Stop session",
       "interrupt": "Interrupt current turn",
-      "queued": "Queued — sends after the current turn"
+      "queued": "Queued — sends after the current turn",
+      "unqueue": "Remove from queue"
     }
   },
   "missionControl": {