Implement UMO transitions to & from the communal hub

Bug: 311243906
Fix: 311243906
Test: verified UMO transitions to & from keyguard and dream
Test: atest CommunalTransitionViewModelTest
Test: atest MediaHierarchyManagerTest
Test: atest LockscreenToGlanceableHubTransitionViewModelTest
Test: atest GlanceableHubToLockscreenTransitionViewModelTest
Flag: ACONFIG com.android.systemui.communal_hub TEAMFOOD
Change-Id: Ib0ac59d2d7f8d36ca9de8bf6041e75e1932b9c1e