Update requirements.txt

requirements.txt

@@ -29,9 +29,10 @@ google-generativeai>=0.8.0
 litellm>=1.0.0
 
 # AWS Bedrock + LangChain (for fallback system)
-langchain>=0.3.0
-langchain-aws>=0.2.0
-langchain-core>=0.3.0
-langchain-community>=0.3.0
+# Using 0.2.x for AgentExecutor compatibility
+langchain==0.2.16
+langchain-aws==0.1.17
+langchain-core==0.2.38
+langchain-community==0.2.16
 boto3>=1.34.0
 botocore>=1.34.0