Composite returns a handler that iterates all HandleFuncs.

ExtractUserInfo will extract the oidc.UserInfo from the request.

OIDCAuthenticator returns a HandleFunc who authenticates a user with the provided issuer using an access_token attached to the request.

RequireAuthentication provides a HandleFunc who ensures the authenticated user is allowed to issue the request.

TokenReceiver is some rough code that should allow a command line tool to receive a token and invoke the provided callback function when a successful exchange is performed.

ClientConfig is used by most processes and handles verifying user authentication.

Config is predominantly used by the `login` command, but is located here to keep the structure between it and ClientConfig similar.

HandleFunc defines a generic function for handling authentication and authorization.

TokenCallback is invoked by the TokenReceiver endpoint when we've successfully received and validated the authenticated user session.