### NEW FEATURES
[1] **NEW FEATURE**: Void World RTP Support - new `VOID` world type for skyblock, oneblock, and void arena worlds
[2] NEW: `void_world.spawn_y` config option (default: 64) - configurable Y level for void world spawns when no solid ground exists
[3] NEW: Void worlds prefer solid ground when available (platforms, islands) and fall back to spawn_y only when the world is truly empty
[4] NEW: Full biome restriction and region protection support in void worlds
### CRITICAL FIXES
[5] **FIXED**: Inventory drag exploit affecting ALL server GUIs
[6] **FIXED**: Folia threading violation in onPlayerDropItem - accessing ItemEntity state from wrong region thread caused IllegalStateException on Folia/Canvas servers. Now checks setup mode first (skips entity access for 99.9% of events) with safe fallback for cross-region edge cases
### IMPROVEMENTS
[7] IMPROVED: Update checker endpoint issue fixed
[8] IMPROVED: Void world spawn Y is bounds-checked against world min/max height to prevent out-of-bounds errors
[9] IMPROVED: SafetyValidator correctly skipped for void world locations to prevent false rejections
### CONFIGURATION
[10] CONFIG: New `VOID` option in `world_types` section - set any world to `"VOID"` for void world RTP support
[11] CONFIG: New `void_world` section with `spawn_y` setting for void world spawn height
[12] CONFIG: All changes fully backward compatible