Yellow squiggly lines begone!
Done automatically on .cpp files through `run-clang-tidy`, with manual corrections to the mistakes.
If an import is directly used, but is technically unnecessary since it's recursively imported by something else, it is *not* removed.
The tool doesn't touch .h files, so I did some of them by hand while fixing errors due to old recursive imports.
Not everything is removed, but the cleanup should be substantial enough.
Because this done on Linux, code that isn't used on it is mostly untouched.
(Hopefully no open PR is depending on these imports...)

Not sure when or why this became necessary but it works.

Most of these changes are to improve consistency in capitalization.

RetroAchievements - Dialog Visual Improvements

Update Achievement List when Rich Presence Updates

Whenever a request to update the Rich Presence comes in, typically every ten seconds, the Achievement Progress Widget will update the sort order of the achievements and all of their measured values.