Fix Dockerfile for HF Spaces - use requirements.txt, port 7860, uvicorn

Force rebuild with pymupdf

Update README.md

Deploy from GitHub Actions

Add pymupdf for ArXiv PDF loading

Update requirements.txt with specific versions from pyproject.toml

Fix langchain chains and retrievers imports for 0.3.x

Fix all langchain.schema imports to langchain_core.documents

Fix LangChain imports for 0.3.x compatibility

Fix Dockerfile for HF Spaces

Initial deployment to Hugging Face Spaces