Live UI: A Shared HUD for Multi-Plugin Servers

Live UI solves Hytale's single-HUD constraint with WORLD-SCOPED entries. Register with forPlayer(uuid, world).entry("plugin:name").label().value().register(), show with show(uuid, world, playerRef, store, entityRef), update with updateValue(uuid, world, entryId, value) or updateValueAllWorlds(), and clean up with unregisterAll(uuid, worldId, pluginId). Critical: register AFTER player arrives in target world, not before teleportation.