Distant Horizons - Au Naturel Edit

Render Thread Optimizations

• Replace synchronized beacon lists with CopyOnWriteArrayList for lock-free iteration from render thread
• Convert DebugRenderer to use ConcurrentHashMap and CopyOnWriteArrayList, removing all synchronized blocks
• Add snapshot pattern in BeaconRenderHandler to minimize lock hold time during culling
• Add snapshot pattern in RenderableBoxGroup for lock-free vertex upload
• Cache Mat4f matrices in LodRenderer to eliminate per-frame allocations
• Cache JOML Matrix4f matrices in RenderBufferHandler for frustum culling

I/O Optimization

• Replace byte-by-byte LOD deserialization with 8KB buffered reads for significantly faster chunk loading