Koha::REST::Plugin::Auth::IdP
my $patron = $c->auth->register( { data => $patron_data, domain => $domain, interface => $interface } );
If no patron passed, creates a new Koha::Patron if the provider is configured to do so for the domain.
my ( $status, $cookie, $session_id ) = $c->auth->session( $patron );
Generates a new session.