BedrockChecker

Shared Bukkit-side Bedrock detection for presentation, packets and pack delivery. Floodgate's synthetic UUID survives proxy forwarding without a local Floodgate plugin. The existing dotted-name heuristic is also retained, but a numeric suffix is not required by Floodgate and is not the primary identity signal. Local APIs additionally identify linked accounts with ordinary Java UUIDs. These presentation heuristics must not be used for authentication or permissions.