- note: for paper, the chunk debug command
- rebase IntervalledCounter into util patch
- mcutil diff
- paper debug chunks --async in DedicatedServer
- TODO keep around region file lock?
- mcutil#getTicketLevelFor is wrong, just delete it later

on another note, clean up mcutils...

apply todo in levelmixin

to fix later:
- Change loadedChunkMap in ServerChunkCache to use concurrent long map