Allows you to quickly stop breaking, play the game, then re-enable breaking. useful if you have many active breakpoints, but need to run the game.

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...)

For thread safety, we shouldn't return any pointers or references that
can be used to mutate the state of the PPCSymbolDB. This should be the
final part of making PPCSymbolDB thread safe unless I've missed
something.

Debugger Add note-type symbols .

Notes are separate from function symbols, and can be searched separately.
Unlike functions, notes of different length can overlap each other.
In the instruction window, a note will always display over the function symbol.