TL;DR We'll build the backend for a members-only video library: upload assets as private, create an RSA signing key, mint a short-lived JWT per viewer in a FastAPI endpoint, and hand the player a stream URL plus a thumbnail URL that both carry the token. Then we'll prove the thumbnail is locked too, because that's the one everybody forgets. The naive version of a paywalled video library is: check the session, render a player, done. The .m3u8 URL in that player is public. Anyone who co...