Option to provide AppDelegate for SwiftUI lifecycle etc

[hyouuu]

Should fix #1045 (comment) but I've no idea how to build OneSignal XCFramework to test and haven't touched ObjC for ages so might have issues

---

This change is 

[jkasten2]

@hyouuu Thanks for the PR! From a quick look it seems this could cover the UIApplicationDelegateAdaptor case in issue #1045. However we first would like an investigation if it is possible to auto detect this and correctly handle it without needing a new API and requiring extra setup steps from app developers.

[hyouuu]

Great to hear! I built a local XCFramework and unfortunately setting the appDelegate wouldn't work as it doesn't seem to respond to the objc selectors. So I added back a OSNotificationReceivedBlock similar to 2.x which works for my project.

Nonetheless I left the changes here in case it would be helpful when you implement the redirection to UIApplicationDelegateAdaptor.

IMO there is no reason to omit OSNotificationReceivedBlock when there are OSNotificationWillShowInForegroundBlock & OSNotificationOpenedBlock

[emawby]

closing this pr since we are fixing in #1091