Add and plumb PromotedNotificationContentModel

This will be used by both the AOD skeleton RON view and the status bar
chips for RONs.

Bug: 369151941
Test: builds
Flag: android.app.ui_rich_ongoing
Flag: com.android.systemui.status_bar_notification_chips
Change-Id: I740c136e67fbbd80e73ee3a8b83ae8e73ca3a990