Added support to animate transitions for menu radii

When dragged by the user, FAB has rounded edges on all sides.
When attached to the side of the screen, that side of the menu flattens to lie uniform.
This aims to smooth out the transition.

Adds a RadiiAnimator to use a single ValueAnimator to drive 8 radii.

Bug: 281140482
Test: atest RadiiAnimatorTest
Flag: ACONFIG com.android.systemui.Flags.floating_menu_radii_animation ENABLED
Change-Id: Ia77bc87905f1d863be713f7e51fc91988819bea8