[Fabric 1.20] Guest Login System aka optional registration

[Fenix5fire]

Implemented Guest Login system. This allows to make registration optional rather than required (configurable, default=false). Guests are considered authenticated but marked as guest. Guests do not have sessions.

Added option to force all guest players with Operator status to register (configurable, default=true)

TODO: Permissions support Separate 'allow X' config for guests Probably change some commands and add more messages to be more clear when dealing with Guests