Update requirements

Author: ajosh0504

requirements.txt

@@ -1,11 +1,10 @@
-pymongo==4.11.3
 langchain==0.3.27
 langchain-aws==0.2.35
 langchain-google-genai==2.1.4
 langchain-openai==0.3.16
-langgraph==0.6.11
-langgraph-checkpoint-mongodb==0.2.1
+langgraph==0.4.2
+langgraph-checkpoint-mongodb==0.1.3
 tiktoken==0.9.0
 voyageai==0.3.4
 tqdm==4.67.1
-Pillow==11.1.0
+Pillow==11.1.0