Improvements

- New indicators when building a Mineral Extractor that point towards the nearest instance of a Mineral Deposit for each mineral type.
- New help text to help explain how existing mineral spikes must be removed before building a Mineral Extractor.

Bug fixes

- Fixed an issue where crystal crabs would do a collision check on water that would crash the game.
- Fixed an issue where using the unstick command would sometimes get players stuck in an infinite loop.
- Fixed an issue where attempting to check for valid belt placement would crash the game.