Adds SystemUI DeviceStateManager utilities

Adds a DeviceStateManager kosmo that provides helper state
information that can be used in tests.

Also updates the Utils#isFoldable method to use the
updated DeviceState#hasProperty method, to be used by
clients within SystemUI.

Test: UtilsTest
Bug: 336640888
Flag: android.hardware.devicestate.feature.flags.device_state_property_migration
Change-Id: I777f7702df01e34546afb147cf2adda2dd39e0f7