feat(gui2): Complete EventEmitter integration

gui_2.py

@@ -239,6 +239,7 @@ class App:
         ai_client.comms_log_callback = self._on_comms_entry
         ai_client.tool_log_callback = self._on_tool_log
         mcp_client.perf_monitor_callback = self.perf_monitor.get_metrics
+        self.perf_monitor.alert_callback = self._on_performance_alert
 
         # AI client event subscriptions
         ai_client.events.on("request_start", self._on_api_event)
@@ -404,6 +405,17 @@ class App:
         with self._pending_gui_tasks_lock:
             self._pending_gui_tasks.append({"action": "refresh_api_metrics", "payload": payload})
 
+    def _on_performance_alert(self, message: str):
+        """Called by PerformanceMonitor when a threshold is exceeded."""
+        alert_text = f"[PERFORMANCE ALERT] {message}. Please consider optimizing recent changes or reducing load."
+        # Inject into history as a 'System' message
+        with self._pending_history_adds_lock:
+            self._pending_history_adds.append({
+                "role": "System",
+                "content": alert_text,
+                "ts": project_manager.now_ts()
+            })
+
     def _process_pending_gui_tasks(self):
         if not self._pending_gui_tasks:
             return