QuickLook swipe down and less message motion when coming back from GiveBackMyFirstResponder

[Amzd]

This PR makes the image preview (quicklook) able to be dismissed by swiping down, instead of the default popGestureRecognizer. This is an improvement because A; the popGesture is only enabled when the navigation bars are shown, B; it interferes with swiping to previous image, and C; the animation feels good.

For this to look good I had to reduce the motion on messages when presenting/dismissing view controllers some more. Now after a view is dismissed the scroll updating is delayed by 0.5s which means that first; the ChatViewController can become firstResponder (bringing up the accessory) and then; the text field can become firstResponder (bringing up the keyboard) without the chat scrolling.

Quick Look Dismiss

Before	After
RPReplay_Final1736090240.mp4	RPReplay_Final1736090333.mp4

Reduced motion

Before	After
RPReplay_Final1736090019.mp4	RPReplay_Final1736089664.mp4

[r10s]

hm, i am not sure i got the gist of this PR completely.

• swipe-down-to-exit-gallery worked also before, and at least on iOS 18, even smoother:

  • really only the image is swiped down, not the whole screen including black borders - this looks esp weird for landscape images
  • no 1-second-delay before the message view with the image is shown again

• opening the gallery without any controls to share etc. may be unexpected: none of whatsapp or telegram do that. the controls only disappear on a second tap

• the message view scrolling in-sync with the gallery left/right: not sure if that is expected by the user or not - whatsapp does it, telegram does not

• the reduced motion is nice

however, always good to have options, so thanks for diving into that. and as said, sorry, if i missed sth.

[Amzd]

TODO: on iOS 18 the keyboard is hidden after viewing a photo, can be fixed by a GiveBackMyFirstResponder extension for UINavigationController.pushViewController(_: QLPreviewController) that does the same as UIViewController.present(_: QLPreviewController)

[Amzd]

Scratch that, that opened a massive can of worms. On iOS 18 the keyboard is just hidden when you click on an image in chat and it does not come back automatically, this is a fine UX I think (and not changed by this PR).