I’m mocking up a web server in rust that could be used for this. Unsure how to verify payments without holding funds, but otherwise it can manage the requests and handle the pubkey auth. I’ll open source if I get it functional.
nostr:note1q9e3kjuqk8fynx3h2qs65q0dx90w447kd3zue7zwnjfr2fglg9dqpj9wev