auth0/go-auth0 ? reverse-engineered prompt

Build me a Go library for Auth0 that makes it easy to talk to both the Authentication API and the Management API.

I want it to feel simple for developers, with clear client setup using a tenant domain and either a token or client credentials. It should support common things like signing users up, logging in with OAuth flows, and calling admin style management actions against an Auth0 tenant. Please include good examples for the most common use cases, and make the API feel clean and easy to discover.

I also want solid docs, helpful error handling, and tests so it is reliable to use in real projects. If you need to check current Auth0 docs while building it, go ahead and look them up online.