apple-system-integration

Integrate an app with Apple system services: calendars/reminders, notifications, Siri/Shortcuts, background execution, and widgets/Live Activities. Covers EventKit (EKEventStore, iOS 17+ write-only vs full-access authorization, EKEvent/EKReminder CRUD, recurrence with EKRecurrenceRule, change notifications), UserNotifications (UNUserNotificationCenter authorization, UNCalendarNotificationTrigger/UNTimeIntervalNotificationTrigger, actions/categories, rich attachments, delegate handling, badge management), App Intents (AppIntent, @Parameter, AppEntity, AppShortcutsProvider, Siri/Shortcuts, interactive snippets), background execution (BGTaskScheduler app-refresh and processing tasks, BGContinuedProcessingTask, background URLSession, Info.plist registration), and widgets/Live Activities (WidgetKit TimelineProvider, App Intent-driven widgets, ActivityKit Activity + Dynamic Island). Use when adding calendar/reminder sync, scheduling local notifications, exposing Siri/Shortcuts actions, running background refresh, or building widgets and Live Activities. Does NOT cover the deep WidgetKit/ActivityKit layout system (use a dedicated widgetkit skill if present), SwiftUI app UI (use swiftui-expert-skill), or on-device AI (use apple-ai).