Provide a self-contained nonce in a publicly accessible endpoint.

Provide nonces for proof of possessions in a manner not requiring the service to save it. The nonce should be used only once. The nonce has a (very) limit lifetime. The response should not be cached. For more information see <a href="https://openid.net/specs/openid-4-verifiable-credential-issuance-1_0.html#section-7.2">OID4VCI Nonce Endpoint specification</a></br> Also provides a DPoP nonce. For more details towards demonstrating proof of possession refer to <a href="https://datatracker.ietf.org/doc/html/rfc9449#name-authorization-server-provid">RFC9449</a>