Update lock task features name and javadoc

Remove reference to recent and replace by overview. Also throw an IAE
if recents is enabled without home.

Also address API council feedback for ActivityOption.setLockTaskMode

Bug: 72807036
Bug: 72799389
Bug: 71790952
Bug: 71866618
Test: atest FrameworksServicesTests:DevicePolicyManagerTest
Change-Id: I70bed3b46137870e6bf0af5bf7f0846dc51f91ab