test(gateway): let the queued-native-image fake accept the persist kwargs

Now that a queued follow-up carries its raw inbound id, the gateway passes
persist_user_platform_id to run_conversation for that turn (run_turn_runner.py
only adds it when inbound_message_id is set). The real AIAgent accepts it; the
test's fake did not. Accept **kwargs, matching the real signature.

tests/gateway/test_queued_native_image_session_key.py

@@ -57,7 +57,9 @@ class CaptureQueuedNativeImageAgent:
         self.tools = []
         self.tool_progress_callback = kwargs.get("tool_progress_callback")
 
-    def run_conversation(self, message, conversation_history=None, task_id=None):
+    def run_conversation(self, message, conversation_history=None, task_id=None, **kwargs):
+        # The real AIAgent.run_conversation accepts the persist_* kwargs the gateway adds for a
+        # message with a raw inbound id (queued follow-ups now carry theirs); tolerate them.
         type(self).calls.append(message)
         return {
             "final_response": f"done-{len(type(self).calls)}",