feat(events): Add EventEmitter and instrument ai_client.py

events.py

@@ -0,0 +1,14 @@
+
+class EventEmitter:
+    def __init__(self):
+        self._listeners = {}
+
+    def on(self, event_name, callback):
+        if event_name not in self._listeners:
+            self._listeners[event_name] = []
+        self._listeners[event_name].append(callback)
+
+    def emit(self, event_name, *args, **kwargs):
+        if event_name in self._listeners:
+            for callback in self._listeners[event_name]:
+                callback(*args, **kwargs)