Update LangGraphAgent to use z-ai/glm-4.5-air model instead of mistralai/mistral-small-3.2-24b-instruct

agent.py

@@ -78,8 +78,7 @@ class LangGraphAgent:
             #     model="gemma-3-27b-it",
             # )
             model = ChatOpenRouter(
-                model="mistralai/mistral-small-3.2-24b-instruct:free",
-
+                model="z-ai/glm-4.5-air:free",
             )
             if model is None and ChatOpenAI is not None:
                 model = ChatOpenAI(
@@ -129,7 +128,7 @@ class LangGraphAgent:
 
     def __call__(self, question: str) -> str:
         state = {"messages": [HumanMessage(content=question)]}
-        result = self.graph.invoke(state)
+        result = self.graph.invoke(state, {'recursion_limit': 10})
         messages = result.get("messages", [])
         # Return only the content after "FINAL ANSWER:"
         for msg in reversed(messages):