Update beatmap online statuses when the set is selected in song select

[bdach]

This is the low effort attempt at fixing #23804 in line with the suggestion from #34112 (comment).

Why low effort?

• It doesn't fix the fact that the same API request is done by two wedges independently despite them being right next to each other (which was the case before I started touching any of this).

  • I could add a caching layer to RealmPopulatingOnlineLookupSource but that would imply that this cache now has to be purged at some point. At what point? Good question. Probably on re-entering song select? Or maybe never (...with the exception of unit tests)?
  • Or I could pull out this online beatmap set fetch to a higher level and pass only the result of it.

• It does a local realm refetch of the status. This is primarily required because of Fix clicking beatmap header causing leaderboard to refresh #33515 - the guard added there prevents the global working beatmap from being refetched with the updated BeatmapInfo via beatmap carousel / detached beatmap store.

• It doesn't address Update button may not show under certain scenarios #20159 because that case concerns difficulties that are present online but missing locally. Resolving that would likely require a new database flag which would feed into

  osu/osu.Game/Beatmaps/BeatmapSetInfo.cs

  Line 107 in 3dced34

  public bool AllBeatmapsUpToDate => Beatmaps.All(b => b.MatchesOnlineVersion);

• I've tested this manually because that's frankly easiest if you have realm studio working (open realm studio, select a beatmap in game, go to realm, change its status to something random, then go back to game, change to another set and change back - the status should revert to what it was). I can add automated tests but it's likely that will be much more annoying to set up.

Please advise how much of the above you'd see addressed and how. PRing as draft pending answers to these concerns.

[peppy]

I've read through the concerns and they all seem valid, but not blockers for getting this in in the current state. Nothing looks critically bad in the diff.

Is that something you could get behind?

[bdach]

if you're ok with the caveats described in the OP I'm ok with undrafting this as-is.

[peppy]

Seems to work