We had some code in VolumeVerifier to catch the error message that
Redump.org used to show when trying to access the Wii datfile without
logging in. This restriction was removed from Redump.org around the
start of 2022, and the code has been unnecessary ever since.

When we added the RetroAchievements integration, we had a discussion
about whether sending version information in the user agent was fine
from a privacy standpoint. We reached the conclusion that it was okay,
but it was conditional on the website having a privacy policy. Neither
incarnation of Redump has that, and Redump also never asked us to send
version information like RetroAchievements did, so let's use a user
agent that just says "Dolphin" when connecting to Redump.

All the staff of Redump (except the absentee sysadmin) have decided to
start a new version of the website at redump.info. It has every disc
from the old site, it has HTTPS, it isn't buckling under the load of AI
scrapers, and moving forward, all adding and verifying of discs is going
to be happening on the new website only. Let's move over.

I've taken the unusual step of updating the translation files manually.
This is because we're very close to a release and because the change is
simple enough that I feel confident about making the change to languages
I don't speak. (I double checked that the Korean translation doesn't
ever follow "Redump.org" by a particle that has a different form
depending on whether there's a final consonant.)

This fixes VolumeVerifier potentially calling TMDReader::GetIOSId for
invalid TMDs.

VolumeVerifier also has a call to TMDReader::GetContent that doesn't
check if the TMD is valid. In practice, this can't get called with an
invalid TMD because the previous commit made it so GetContentOffsets
returns an empty vector if the TMD is invalid, but I've added a check
inside TMDReader::GetContent just to be on the safe side.

I also made VolumeVerifier show a specifically worded problem if the
ticket or TMD is invalid. Before, invalid TMDs in Wii discs and WADs
and invalid tickets in WADs would show a more generic problem.

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...)

DiscIO: Remove redundant qualifiers