Wearable events for AmbientContextManager.

WearableSensingService implements the EVENT_WEARABLE_VENDOR_START AmbientContextEvents that
AmbientContextManager supports. Only AmbientContextRequests of all
events greater than EVENT_WEARABLE_VENDOR_START will be accepeted by the
WearableSensingService. A request with a mixture of event types will not
be accepted. None Wearable events will be delegated to the default
AmbientContextDetectionService on the system.

Bug: 244181656
Test: Builds. atest CtsAmbientContextServiceTestCases atest CtsWearableSensingServiceTestCases
Ignore-AOSP-First: to prevent new feature leak.
API-Coverage-Bug: 259453662
Change-Id: Ib66be763978117f052eed33d66652e34ed655bfc