H0ugetsu/go-medium-clone ? reverse-engineered prompt

Build me a backend API for a Medium style app that follows the RealWorld spec.

I want users to be able to sign up, log in, and get a JWT token, then use that token to create and manage their own articles, comments, favorites, and profile. Public visitors should still be able to browse articles, filter them by tag or author, view profiles, read comments, and see the list of tags without logging in. Logged in users should be able to follow and unfollow other users, see a feed of articles from people they follow, and know whether they are already following or have favorited something.

Please make the API return the same kinds of JSON shapes RealWorld expects, including slug based article URLs, pagination with limit and offset, article and favorite counts, and proper 403 or 422 style errors when someone tries to edit content they do not own or submits invalid data. If you need current RealWorld details, look them up online and match the spec closely.