Function parse_cose_enroll_response 

pub fn parse_cose_enroll_response(
    bytes: &[u8],
) -> Result<EnrollResponse, AuthError>

Verify and decode an enrolment challenge this service signed. The verifying key is derived from the same secret seed ([CHALLENGE_SIGNING_KEY_ENV]): the server checks its own challenge on the way back. It does not check expires_at; the caller must. Was cratestack_auth::parse_cose_enroll_response.