Who would have guessed that `Schedule` calls were there for a reason!
I've tidied things up. Most of the changes I've made here are not
required – the schedule is the main thing here. The reason the sound was
playing is because one-too-many schedules was removed causing beatmap
updates to update carousel specifics while still at the player loader
screen.
Note that the selection sound still plays on returning to song select,
but this is not a regression. I'm looking at fixing this in a separate
PR because I'm in a good place as far as understanding the logic right
now and it would be a waste to leave it broken.
Closes https://github.com/ppy/osu/issues/25875.
The fallback to "any of the added sets" needs to be applied after
they've all been added, rather than with every added one. Otherwise, in
flows that expect a particular difficulty to be selected in the end
(such as exiting from editor) would end up switching away from the
edited beatmap.
Regressed in c40c70509e.
As it turns out, `item.Item.Filtered.Value` is not the only condition
that should be checked to determine if a carousel item should be hidden
or not - `item.Item.State.Value != CarouselItemState.Collapsed` should
also be true. This was even available as the `item.Item.Visible`
convenience property, which is used in this commit.
Failing to check `item.Item.State.Value` led to setting non-zero alpha
on collapsed carousel items, leading to phantom beatmap sets appearing,
as the alpha was set in the entire carousel's `Update()` method, thus
firing every frame.