Closes https://github.com/ppy/osu/issues/30163.
If I'm to be blunt, the decoupled stuff in song select makes my head
spin. I spent a solid 20 minutes thinking how I was going to fix this
one but then finally realised that generally most of the cause there
was the fact that `AdvancedStats` was seeing the new rulesets *before*
the "ensure global selected mods are valid for current ruleset" logic,
and so decided to just _delay_ that until the decoupled transfer
thingamajig happens.
I was honestly considering combining `BeatmapInfo`, `Ruleset`, and
`Mods` into one property on `AdvancedStats`. I figured I'd rather not
push my luck and try the baseline version first, but I honestly think
that direction is going to be required at some point to properly corral
all of the decoupled madness taking place in song select.
Whomst've thought this was an ok thing to do? How did this pass review?
Let's leave these as rhetorical questions right now. Huge chances are
I'd implicate myself with at least one of them.
I'm not sure why this was "fine" for as long as it apparently was,
but what `MusicController` was doing was completely incorrect and
playing with fire (accessing raw managed realm objects), which went
wrong somewhere around - admittedly -
https://github.com/ppy/osu/pull/29917, likely because that one started
*storing* these raw managed realm objects to fields, and you know what
will happen to those after you do a migration and recycle realms.
To attempt to circumvent this, (ab)use `DetachedBeatmapStore` instead.
Which does necessitate moving it to `OsuGameBase`, but it's the simplest
way out I can see. I guess the alternative would be to faff around with
`Live<T>` but it's ugly and I'm attempting to fix this relatively quick
right now.
After switching `UserLookupCache` to `GET /users/lookup` from `GET
/users`, multiplayer sort of breaks, since the former endpoint does not
return `ruleset_statistics`, which are used in multiplayer to show
users' ranks. Therefore, switch multiplayer to use the appropriate
request type directly.
Doing this alleviates https://github.com/ppy/osu/issues/29982, as the
currently online display utilises the user lookup cache, and currently
is hitting rate limits due to the amount of data retrieved from the `GET
/users` endpoint. Switching to `GET /users/lookup` reduces the chance of
this happening.
