Microsoft.Identity.Client.Internal.ClientCredential.CredentialTransportProtocol
Determines how the client authenticates when acquiring tokens.
Replaces the confusing pair of boolean flags previously used to signal mTLS vs. regular flows.
Mtls = 1
mTLS authentication: the credential must supply a certificate for binding to the
TLS transport layer. No client_secret is valid here; JWT-PoP assertions are issued when
a certificate-bound delegate credential is used.
OAuth = 0
Standard OAuth client authentication: client secret, JWT bearer assertion, or JWT-PoP assertion.