Last one before I add the actual linter rules!

Closes #944, closes #532. ~WIP because something is causing the test
budget to fail to create because it’s using INSERT instead of UPDATE sql
queries. (Or not? I have no idea)~

Fixes #615. I would appreciate double-checking that I didn’t
accidentally delete anything that is important.

Since I’m removing the related API methods, this is technically a
breaking change (even if people would have no reason to remove this
stuff), so we should probably do a major release of the API package.

This is the last PR with lots of renaming for `loot-core`!

*  (prettier) adding trailing commas

* More commas