Module registration 

Client registration and redirect-URI resolution: RFC 7591 Dynamic Client Registration (POST /register) and the redirect_uri trust boundary shared by DCR-registered clients and CIMD client_ids (see crate::cimd). Split out of authorize.rs to keep that module under the repo’s file-size contract — authorize() itself still lives there and calls resolve_client_redirect_uris from here.

Enums

RegistrationError

RFC 7591 §3.2.2 requires /register errors to be reported as HTTP 400 with a {"error": ..., "error_description": ...} body using one of the RFC’s defined error codes — unlike the generic AuthError -> IntoResponse impl in error.rs, which returns 422 with a {"kind", "message"} body. This is register_client’s dedicated error type, mirroring TokenEndpointError in token.rs for the /token endpoint (RFC 6749 §5.2).

Functions

register_client