This update attempts to resolve some timeouts/crashes when loading chunks.

• Only spawn item_frames in the end when the chunk has completely loaded.
• Removed shipwreck_map loot table. This should help mitigate an issue where the server would load lots of chunks searching for a feature which does not exist in a SkyGrid world (buried treasure). Treasure maps may still be generated by villagers, but that will hopefully be much less common.

Please let me know if you are still seeing timeout warnings, and paste the warnings if you are.