feat(native): add iOS home screen widgets for continue watching and upcoming

- Add `ContinueWatching` (systemSmall) and `Upcoming` (systemSmall) SwiftUI widgets via `expo-widgets`, registered in `app.json` under the `group.com.jakejarvis.sofa` app group
- Add `widget-images` local Expo module with a Swift `WidgetImagesModule` that downloads and resizes remote poster images into the shared app group container for use by widgets; also copies bundled assets (sofa icon fallback)
- Add `src/lib/widgets.ts` to fetch dashboard data, cache poster images, and write a JSON timeline to the shared container via `expo-widgets`
- Add `ContinueWatching` and `Upcoming` SwiftUI widget views in `src/widgets/`
- Add `useWidgetRefresh` hook that refreshes widgets on foreground (throttled to once per minute) and on session ready
- Debounce widget refresh in `invalidateTitleQueries` so rapid mutations (e.g. marking multiple episodes watched) batch into a single refresh
- Expose `titles.upcoming` from the dashboard procedure and add `upcomingTitles` field to the dashboard schema
- Bump iOS deployment target to 16.2 (required by WidgetKit timeline APIs)

apps/native/modules/widget-images/src/WidgetImagesModule.ts

@@ -0,0 +1,3 @@
+import { requireNativeModule } from "expo-modules-core";
+
+export default requireNativeModule("WidgetImages");