signUp abstract method
Authenticates a new user using a TOTP.
This function creates a new user identified by loginId
and
the optional information provided on via the details
object.
It returns a TotpResponse.key (seed) that allows
authenticator apps to generate TOTP codes. The same information
is returned in multiple formats.
Implementation
Future<TotpResponse> signUp({required String loginId, SignUpDetails? details});