Preserve hold past loading screen on touch.

[Hissymaster]

You might be confused on the glance of the title suggests, so hear me out.

Put it simply, Touching and holding on the loading screen does not make the gameplay use the finger you touch and held with your "tracking" finger.

As follows is what currently happens:

Screen_Recording_20250124_235319.mp4

you will notice, despite me clearly having a finger over the circles, and me tapping the side tk the rythm, it all results in misses.

to put a long story short, the touch and hold that was started on the load screen does nothing, so you have to let go, then touch and hold again to have the gameplay begin to actually track using that finger.

This is a bit inconvinient, and could leave players confused.

I am unsure about the logic behind the touch controls of osu, but put it simply, the touch and hold should continue into the gameplay.

[peppy]

Might be a hard one to fix, and it's probably not going to affect many users, but we'll keep tracking this one. (also I'm sure this is not the first time this has been reported, and a fix may have event been attempted)

cc @frenzibyte

[frenzibyte]

This issue is directly happening because the user touched the screen before the gameplay's input manager was added to the scene, and because we're not syncing input when the input manager is added (i.e. on PassThroughInputManager.LoadComplete), OsuTouchInputMapper is not aware about the touch and can never be aware of it without the input manager being synced first.

This roots back to the same issue that #29090 suffered from and which ppy/osu-framework#6398 attempted to fix before it derailed to debate and confusion.

I consider this issue to be crucial to the iOS release and I've already highlighted in #31419 (comment) (see last bullet point in the "side notes" section). I will take one more attempt on this.