Completes consumer consent registration after the OAuth 2.0 Authorisation Code
flow. The supplier resolves consumer identity from the token, records consent
against the MPXN, and returns a registration_id for managing the relationship.
Consent can be granted for a one-off access or open-endedly until revoked.
OAuth 2.0 Authorisation Code flow for RTI User authentication and consumer consent.
Each supplier operates its own OAuth server. In production, substitute the
placeholder host with the relevant url from the Supplier Register.
OpenAPI does not permit URI templates in security scheme URLs, so a placeholder
is used here.
No body required. Consumer identity is resolved from the OAuth token.
Empty body — consumer identity is derived from the bearer token.
Consent registered. Returns the registration ID and in-scope metering points.