fix chat error

LG_agent.py

@@ -1,16 +1,19 @@
-from langchain_huggingface import ChatHuggingFace
+from langchain_huggingface import HuggingFaceEndpoint, ChatHuggingFace
 from typing import Annotated, TypedDict
 from langgraph.graph.message import add_messages
 from langchain_core.messages import HumanMessage, AIMessage
 from tools import search_duckduckgo
 from langgraph.prebuilt import tools_condition
 
-chat = ChatHuggingFace(
-    repo_id="google/flan-t5-small",  # Small and fast
+
+llm_endpoint = HuggingFaceEndpoint(
+    repo_id="google/flan-t5-small",
     temperature=0,
     model_kwargs={"max_new_tokens": 512}
 )
 
+chat = ChatHuggingFace(llm=llm_endpoint, verbose=True)
+
 tools = [search_duckduckgo]
 chat_with_tools = chat.bind_tools(tools)