Fix langgraph kwargs error

src/agent.py

@@ -75,6 +75,7 @@ If the user asks to scrape utility data, run the utility scraper, or fetch utili
 If they ask for a reminder, use the `set_reminder` tool and pass {target_jid} as the target_jid!
 """
     
-    agent = create_react_agent(llm, tools, state_modifier=system_prompt)
+    # Use state_modifier or prompt depending on langgraph version, falling back to older syntax if needed.
+    agent = create_react_agent(llm, tools, messages_modifier=system_prompt)
     result = agent.invoke({"messages": [("user", user_request)]})
     return result["messages"][-1].content