feat(worker): remove a queued interactive message

StreamingClaudeSession.RemoveQueuedAsync drops the first occurrence of a queued
message from _pending and re-broadcasts the updated queue. Wired through
InteractiveSessionService + WorkerHub.RemoveQueuedInteractiveMessage +
IWorkerClient.RemoveQueuedInteractiveMessageAsync. Removal by text (first match)
is robust to a turn flushing mid-click. Fakes + ILiveSession impls updated.

tests/ClaudeDo.Ui.Tests/StubWorkerClient.cs

@@ -148,6 +148,12 @@ public abstract class StubWorkerClient : IWorkerClient
         SentInteractive.Add((taskId, text));
         return Task.CompletedTask;
     }
+    public List<(string TaskId, string Text)> RemovedQueued { get; } = new();
+    public virtual Task RemoveQueuedInteractiveMessageAsync(string taskId, string text)
+    {
+        RemovedQueued.Add((taskId, text));
+        return Task.CompletedTask;
+    }
     public List<string> StoppedInteractive { get; } = new();
     public virtual Task StopInteractiveSessionAsync(string taskId)
     {