feat(worker): broadcast interactive message queue + delivery

StreamingClaudeSession raises onQueueChanged (pending snapshot) and onUserMessageSent
(on delivery, incl. the seeded first prompt); InteractiveSessionService forwards these
as InteractiveQueueChanged/InteractiveMessageSent broadcasts. Lets the UI show queued
messages above the input and move a message into the transcript only when actually
delivered to Claude. Client events + fakes updated.

src/ClaudeDo.Worker/Hub/HubBroadcaster.cs

@@ -83,4 +83,10 @@ public sealed class HubBroadcaster : IPrimeBroadcaster, IRefineBroadcaster
 
     public Task InteractiveSessionEnded(string taskId) =>
         _hub.Clients.All.SendAsync("InteractiveSessionEnded", taskId);
+
+    public Task InteractiveQueueChanged(string taskId, IReadOnlyList<string> pending) =>
+        _hub.Clients.All.SendAsync("InteractiveQueueChanged", taskId, pending);
+
+    public Task InteractiveMessageSent(string taskId, string text) =>
+        _hub.Clients.All.SendAsync("InteractiveMessageSent", taskId, text);
 }