Distant Horizons - Au Naturel Edit

Playing around in Performance Optimizations for Lod Building while procrastinating looking into OPEN GL :)

Tier 1: Quick Wins

• Priority 1.1: Replace IntArrayList with IntOpenHashSet for Y-transitions in upsampling
• Priority 1.2: Add biome-based tint color caching to avoid redundant color calculations
• Priority 1.3: Guard API event firing with listener check to skip serialization when no listeners registered
• Priority 1.4: Pre-cache biomes per column to eliminate repeated biome lookups during vertical iteration
• Priority 1.5: Use incremental hash code updates instead of full recalculation on each modification
• Priority 1.6: Cache snow layer block states per level to avoid repeated registry lookups

Tier 2: Medium-Effort High-Value

• Priority 2.1: Use ID-based block filtering with IntOpenHashSet instead of wrapper HashSet.contains()
• Priority 2.2: Fix instance-scoped reverse lookup map - populate idMap during deserialization
• Priority 2.4A: Use guess-based wrapper in height map creation

Bug Fixes

• LodQuadTree: Fix concurrent modification exception when nodesNeedingRetrieval HashSet was modified while being converted to ArrayList in async thread
• FullDataPointIdMap: Fix deserialization not populating the reverse lookup idMap, which caused lookup failures after loading chunks from disk

Other Changes

• Remove C2ME detection and warning code (not applicable when running via Sinytra Connector)
• Remove Chunky detection and warning code (intentionally allowed to be used together in this build)