feat: mini-rag activity done

add image to readme.md

Update README to remove project structure details

feat: langgraph rag pipeline

centralize local llm config && local embeddings

feat: add linear RAG query chain with local LLM

modify gitignore

ignore local vector database chroma_wiki

feat: functional RAG indexing with local ChromaDB and Ollama

create README.md file

initial commit: create API based on local llama3