Reland "Update Glanceable Hub's AppWidgetHostListener impl for widget events"

This change updates GlanceableHub's custom AppWidgetHostListener
implementation to add support for the new collectWidgetEvents method.
This enables event reporting for the hub's widgets.

This reland also adds calls to
AppWidgetHostView.start/stopVisibilityTracking to record visibility
durations of individual widgets.

Bug: 429228078
Test: Manual, use widgets on mobile hub and confirm that they are
 reported
Test: atest SystemUITests --test-filter="com.android.systemui.communal.widgets.*"
Flag: android.appwidget.flags.engagement_metrics
Change-Id: I8204c04582cb5e0e59a5375cd75f8e928cbe157e