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...)

Use "bzip2" instead of "bzip" in optparse's compression choices for the
convert command. This is both more accurate and matches what the
ParseCompressionTypeString function expects.

The mismatch between the two parsing functions prevented compression
using bzip2 because either ParseCompressionTypeString or optparse would
generate an error when using "bzip" or "bzip2" respectively.

Fixes https://bugs.dolphin-emu.org/issues/13427

DolphinTool: Use {fmt} library