Revise requirements.txt with updated dependencies

Updated LangChain packages and added cassio dependency.

requirements.txt

@@ -1,32 +1,34 @@
-# Core
+# ==================== Core Framework ====================
 streamlit==1.31.0
 python-dotenv==1.0.0
 
-# LangChain (keep only the main package you use)
+# ==================== LangChain Ecosystem ====================
 langchain==0.1.16
+langchain-community==0.0.38
+langchain-core==0.1.46
+langchain-groq==0.1.3
+langchain-huggingface==0.0.1
+langgraph==0.0.43
+langchainhub==0.1.15
 
-# Vector/Embeddings - sentence-transformers requires torch
-# Add a torch dependency to satisfy sentence-transformers. Adjust version if needed for your environment.
-torch>=2.0.0
-sentence-transformers==2.5.1
-
-# Optional vector DB (uncomment if required and verified)
+# ==================== Vector Database & Embeddings ====================
 cassio==0.1.4
+sentence-transformers==2.5.1
 
-# Document processing
+# ==================== Document Processing ====================
 tiktoken==0.6.0
 beautifulsoup4==4.12.3
 lxml==5.1.0
 
-# External APIs & tools
+# ==================== External APIs & Tools ====================
 wikipedia==1.4.0
 arxiv==2.1.0
 
-# Data & utilities
+# ==================== Data & Utilities ====================
 pandas==2.2.1
 pydantic==2.6.4
 typing-extensions==4.10.0
 
-# Optional: Performance & Monitoring (comment in only if needed)
+# ==================== Optional: Performance & Monitoring ====================
 # psutil==5.9.8
 # prometheus-client==0.20.0