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...)

RetroAchievements - Dialog Visual Improvements

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.

When AchievementProgress::UpdateData(false) is called, it will now empty itself and reinsert all existing boxes, re-sorted into their current buckets, and call UpdateProgress on them all.

rc_client provides basic sorting buckets as a possible option when retrieving the list of achievements or leaderboards; this enables them and labels them in the dialog.

UpdateData in AchievementsWindow now only updates the components being requested, massively improving the window's performance. The parameter is UpdatedItems in AchievementManager, which tracks which portions of the system have been updated for every update callback.

AchievementProgressWidget maintains in memory a map of AchievementBox pointers so that UpdateData can operate on them individually. UpdateData is overhauled for three options: UpdateData(true) will destroy the entire list and re-create it from scratch as before, to be used if the game or player changes/closes/logs out. UpdateData(false) will loop through the map and call UpdateData on every achievement box, to be used for certain settings changes such as enabling badges or disabling hardcore mode. UpdateData(set<IDs>) will call UpdateData on only the IDs in the set, to be used when achievements are unlocked.

AchievementBox is an extension of QGroupBox that contains the data for a single achievement, initialized with the achievement data and able to reference AchievementManager to update itself.

This makes the API a little nicer to use, since you don't need to do
a mandatory dereference when passing the lock into any kind of scope
guard.