Update deployment constraints for python-magic-bin

Updarte chatbot with deployment configurations on the Render

Changes to be committed:

Implementation for Google drive is done. Now it is working fine, except need a new function that can delete the chunks if a document is removed from google drive.

Enhanced the support for the excel file and added endpoint to have optimized vector store and Rag for the Excel.

Working chat with context and history

Setup completed

Refactoring code

Added support for multiple LLMs