Fix buggy interactions, and make coordinates easier to reason about

[soundofspace]

What has been done so far:

• Introduce position for absolute, relative viewport, and relative mouse
• Utility function to convert between them
• Migrate decent amount of logic to these new types
  • Main benefit is to communicate coordinates better instead of reusing x,y everywhere and having to think about this every time
• Fix scrolling not working as intended when using coordinates (current solution feels hacky, but will be much better once switched to absolute coordinates)
• Fix/improve rectUtils: contained bugs (and weird edge cases), also added new util function

TODO:

• Migrate as much as possible/where it makes sense to absolute coordinates, why:
  • Extract out extra info needed such as scrollposition, relativeTo... (encoded in absolute position) This info is only needed again when converting happens -> don't clutter everything with this
  • Much easier to reason about coordinates in absolute system
  • When other unit are needed don't reinvent the wheel everywhere, but just use util functions to convert between coordinate systems
• Tests for new rectUtils, and coordinateUtils
• Cleanup old logic and leftovers
• Modify Hero where needed
• ...