In iOS 18.4, UIKit started logging warnings that apps need to migrate to UIScene lifecycle

CLIENT OF UIKIT REQUIRES UPDATE: This process does not adopt UIScene lifecycle. This will become an assert in a future version.

https://developer.apple.com/documentation/technotes/tn3187-migrating-to-the-uikit-scene-based-life-cycle

Flutter design doc: https://docs.google.com/document/d/1ZfcQOs-UKRa9jsFG84-MTFeibZTLKCvPQLxF2eskx44/edit?tab=t.0

This is a tracking issue to track issues and progress related to this migration.