Ambient AOD support

Enables transparency on the light reveal scrim, if supported by
the current wallpaper. However, while transitioning from
GONE->AOD, always be fully opaque as the underlying surface is
still visible until the device is fully in AOD.

Bug: 373844670
Test: atest LightRevealScrimInteractorTest
Flag: com.android.systemui.shared.ambient_aod
Change-Id: Iaec877432176d5436d284c00e09c7f985927eeab