Add graceful error handling for unknown/malformed session events in Python SDK

Co-authored-by: friggeri <106686+friggeri@users.noreply.github.com>

Author: Copilot

python/copilot/client.py

@@ -726,7 +726,11 @@ def handle_notification(method: str, params: dict):
                 session_id = params["sessionId"]
                 event_dict = params["event"]
                 # Convert dict to SessionEvent object
-                event = session_event_from_dict(event_dict)
+                try:
+                    event = session_event_from_dict(event_dict)
+                except Exception:
+                    # Silently ignore unknown/malformed event types for forward compatibility
+                    return
                 with self._sessions_lock:
                     session = self._sessions.get(session_id)
                 if session:
@@ -801,7 +805,11 @@ def handle_notification(method: str, params: dict):
                 session_id = params["sessionId"]
                 event_dict = params["event"]
                 # Convert dict to SessionEvent object
-                event = session_event_from_dict(event_dict)
+                try:
+                    event = session_event_from_dict(event_dict)
+                except Exception:
+                    # Silently ignore unknown/malformed event types for forward compatibility
+                    return
                 session = self._sessions.get(session_id)
                 if session:
                     session._dispatch_event(event)