Unified logic to set restriction type add_type_restriction_func.

AddVerificationParamsHandler handles adding verification parameters in a single step /add_verification_params.

/check_admin command - check administrator rights in a group and verify verification parameters.

Handler deleting all verification parameters for a group /delete_all_verification_params.

Store change listener.

ListVerificationParamsHandler displays the list of added verification parameters /list_verification_params.

A new user has joined the group.

Handler to switch active verification parameters /set_active_verification_params.

Handler for /set_type_restriction.

/setup command - administrator initiates configuration.

Handler for /start.

Handler for /test_verification.

heandler for /verified_users_list.

Handler /verify.