Issue #12043 requested adding FastAPI learning resources. The requested O'Reilly title "FastAPI: Modern Python Web Development" appears to be a paid book, so instead this PR adds two free, authoritative FastAPI resources:



- FastAPI official docs: https://fastapi.tiangolo.com/ (tutorial + reference)

- Tutorialspoint FastAPI PDF: https://tutorialspoint.com/fastapi/fastapi_tutorial.pdf



Both are free and legal to link to; added them alphabetically to the Python section in books/free-programming-books-langs.md.



I verified both links on 2025-10-30. See #12043 for the original request.

