auth0/java-jwt ? reverse-engineered prompt

Build me a Java library for working with JSON Web Tokens on the server side.

I want to be able to create a token, add common claims like issuer and custom data, sign it with a secret or with RSA or ECDSA keys, then verify it later and get clear errors if the signature or required claims are wrong. Please make it work cleanly on Java 8, 11, 17, and 21, and include examples for the common cases so it’s easy to copy into a backend app. Support the usual JWT signing and verification algorithms, and make the API feel simple enough that I can generate a token in a few lines and validate it with a reusable verifier. If you need to check current Java or crypto docs online while building it, go ahead.