SayanVanish

chore(bukkit): better discordsrv support and new isOnQuit vanish option api

chore(bukkit): keep flying state in toggle sneak gamemode feature

fix(bukkit): prevent fake join/quit message on /sayanvanish <player> command if the player is offline

fix(bukkit): disabling checkPermissionOnQuit caused all players to get vanished upon join

chore(proxy/velocity): rename online_players feature to updating_ping

fix(bukkit): don't trigger discordsrv join/quit message if the vanish/unvanish event is called upon join