Remove dead updateLayout JS→native bridge path

Now that both platforms observe content height natively (iOS via KVO,
Android via OnLayoutChangeListener), the JS-callable updateLayout()
is unused. Remove:

- updateLayout() and prevLayoutDetentIdentifier from iOS SheetView
- AsyncFunction("updateLayout") from both platform module definitions
- updateLayout method from the JS BottomSheetNativeComponent

Android's updateLayout() is kept as a private implementation detail
since the keyboard insets listener and native layout observer both
call it internally.

https://claude.ai/code/session_01Rp7ef1h3fKh6fhStcjqLJ5

modules/bottom-sheet/ios/BottomSheetModule.swift

@@ -19,10 +19,6 @@ public class BottomSheetModule: Module {
         view.dismiss()
       }
 
-      AsyncFunction("updateLayout") { (view: SheetView) in
-        view.updateLayout()
-      }
-
       Prop("cornerRadius") { (view: SheetView, prop: Float) in
         view.cornerRadius = CGFloat(prop)
       }