Timeout app predictions after 12 hours

Ignore predicted bucket if it's been too long since the
last update, and use internal timeout logic to set
standby buckets.

Keep track of last predicted time and persist it.

Bug: 70219058
Test: atest FrameworksServicesTests:AppStandbyControllerTests

Change-Id: Ib2992201d204b92fdd4a0a00754d81e7bbfc292f