Notification unbundle/rebundle on adjustment type updates

 Trigger notification unbundling/rebundling when adjustments are enabled/disabled from Settings.
 Save classification in NotificationRecord and apply when adjustments are enabled.

Flag: android.service.notification.notification_regroup_on_classification
Test: atest NotificationManagerServiceTest
Test: atest GroupHelperTest

Bug: 382047364
Bug: 377697247

Change-Id: Ic738fd9e5c0f33a1b504aef17b2ba57a68e5ae84