refine response instructions for unanswered queries in RAGService

changes k value to 15

added combined langchain_document content metadata extraction to reduce the calls to llm

changed to groq

fix

switched to openrouter model

reranker added

fixed source doc issue

fix deps

fix deps

added hybrid retriever

removed few shot metadata extraction and added sementic check for same keyword

db fix

fix database

schema fix

changed schema

edited dockerfile and database.py

fix cache issue

code push

initial commit