draft-ietf-oauth-attestation-based-client-auth-07

• remove restrictions to not allow MAC-based algorithms
• require iat in Client Attestation PoP JWT
• clarify use_attestation_challenge and add invalid_client_attestation
• add client_attestation_signing_alg_values_supported and client_attestation_pop_signing_alg_values_supported to IANA egistration
• add implementation consideration for Authorization Server Metadata
• clarify refresh token binding
• check client_id at PAR endpoint
• added use_fresh_attestation as an error to signal that the attestation was not deemed fresh enough by the server
• mandate the defined header fields if the attestation and pop are transferred via header fields