BukkitCustomEntity
Custom Bedrock presentation bound to a real Bukkit entity.
The wrapped entity still exists normally on the server, so AI, damage, persistence, targeting, Bukkit events and plugin interactions keep using the real entity. This handle only prepares Bedrock clients to render that same Java entity id as a registered custom entity and keeps runtime properties in sync.
prepareSpawnFor must be called before the viewer receives the entity spawn packet. If the viewer is already tracking the entity, callers need to force a normal server retrack/respawn before the custom Bedrock definition can take effect.