Allow launcher to control home app surfaces during recents animation

- Previously, the app leashes were reparented to the standard animation
  layer which was always above the home layer. Now we reparent both to the
  home animation layer for the duration of the app-controlled recents
  animation. This allows launcher to reorder the home surface above the app
  during the swipe gesture and draw above the app.

Bug: 70341013
Test: atest FrameworksServicesTests:com.android.server.wm.RecentsAnimationControllerTest
Test: Swipe up, and ensure that the home app surface is also being animated
Change-Id: I2c0fa79c7bc1fffaf1374beb45386faea14ec20c