ActivityKit — Live Activities & Dynamic Island (iOS)

Build and update Live Activities and the Dynamic Island in an iOS app with ActivityKit — ActivityAttributes + ContentState, Activity.request/update/end with ActivityUIDismissalPolicy, ActivityConfiguration + DynamicIsland (compactLeading/compactTrailing/minimal + DynamicIslandExpandedRegion) registered in a WidgetBundle, the Lock Screen presentation, staleDate/relevanceScore, and remote updates via APNs (pushType .token / .channel, pushTokenUpdates, content-state payloads, NSSupportsLiveActivitiesFrequentUpdates + frequentPushesEnabled). Use when starting/updating/ending a Live Activity, laying out the Dynamic Island, or wiring push-to-update. The widget/timeline counterp…