Being able to flip doesn't really feel all that good and `master` was
already clamping, so let's just bring that back for now. Flipping can be
reconsidered in a follow-up if it actually can be made to behave well.
Not only is this simpler, but it also is more correct (for explanation
why, try holding both shift keys while dragging, and just releasing one
of them - the previous code would briefly turn aspect ratio off).
Closes https://github.com/ppy/osu/issues/28216.
The affected user's database contained six sentakki scores with an empty
hash. When an online score is being imported, an online model (which
does not have a hash) will be transmogrified into a `ScoreInfo` with
an empty hash, which would end up accidentally matching those scores
and basically breaking everything at that point.
To fix, avoid attempting to match anything on empty hash. This does not
break online score matching because for those cases the actual online ID
of the score will be used.