Toggle whether custom channel names set with the gvc/name or gvc/rename commands have to be unique or not.
OFF by default.
When turned on, users will be unable to rename their channel if there is another voice channel with the same custom name anywhere in the server.
Note: The check is only done once when renaming the channel, and compares only the name/template itself, not the result of the template being evaluated. E.g. We love
@@game_name@@will be seen as identical to another channel with the same template, even if the game they are playing is different.