- VoxelProviderThread is now VoxelDataLoader and uses generic block manager
- Fixed threads locking up, input mutex was not always unlocked due to for loop exiting early
- Fixed blocks failing to load, region rejection was using invalid pointer
- Fixed block shifting in region rejection, was replacing wrong index in `block_indexes`
- Fixed block region rejection missing blocks, was not stepping back the loop after shifting blocks
- Added output message to notify of block rejection