Lower-level passkey methods for custom authenticator flows and platforms where AuthenticationServices is unavailable (tvOS, watchOS).
These methods handle the network side of the WebAuthn ceremony only — the caller is responsible for driving the platform authenticator between fetching options and submitting the credential response. For an end-to-end flow on iOS 16+/macOS 13+, prefer signInWithPasskey(presentationAnchor:) and registerPasskey(presentationAnchor:).
Passkey support is experimental. Opt in with @_spi(Experimental) import Supabase. The API may change in future releases.