Add split shade blueprint

This begins the separation into a specific large screen
blueprint. Adds logic to KeyguardBlueprintInteractor to determine
which blueprint should be active, based upon configuration.

For the moment, the only thing affected is NSSL placement and will be
followed by media.

Bug: 296370020
Test: atest KeyguardBlueprintRepositoryTest
DefaultKeyguardBlueprintTest KeyguardBlueprintInteractorTest
Test: Use foldables to test layouts
Flag: LEGACY MIGRATE_NSSL DISABLED

Change-Id: I147eb91c89a32c7f1535739f0bcc79d91f29dbf6