PreAuthCode
data class PreAuthCode(val preAuthorizedCode: String, val transactionCode: String? = null) : OAuth2Client.AuthorizationForToken(source)
Pre-auth code from CredentialOfferGrantsPreAuthCode.preAuthorizedCode in CredentialOfferGrants.preAuthorizedCode in CredentialOffer.grants, optionally with a transactionCode which is transmitted out-of-band, and may be entered by the user.