fixed import issue

backend/app/agents/graph.py

@@ -5,7 +5,7 @@ from langgraph.prebuilt import ToolNode
 from langgraph.graph.message import add_messages
 from langchain_openai import ChatOpenAI
 from langchain_core.messages import SystemMessage, HumanMessage, AIMessage, BaseMessage, ToolMessage
-from langgraph.checkpoint.sqlite.aio import SqliteSaver
+from langgraph.checkpoint.sqlite import SqliteSaver
 import sqlite3
 
 from .tools import TOOLS

requirements.txt

@@ -14,3 +14,5 @@ openai==1.40.6
 # LangGraph + sqlite checkpoint
 langgraph==0.2.34
 aiosqlite==0.20.0
+
+langgraph-checkpoint-sqlite==2.0.11