Rename `AuthenticatorDevice` type and usage

[MasterKale]

Describe the issue

I don't like that the "authenticator" argument in verifyAuthenticationResponse() is of type "AuthenticatorDevice". I decided these names four years ago, and in retrospect it should have been called something like Credential instead even back then. I'm updating docs for the v10 release right now and it's really standing out as an odd choice in naming.

Next major release consider renaming these two to reflect changes in the ecosystem since 2020.