feat: beta background sync (#21243)

* feat: ios background sync

# Conflicts:
#	mobile/ios/Runner/Info.plist

* feat: Android sync

* add local sync worker and rename stuff

* group upload notifications

* uncomment onresume beta handling

* rename methods

---------

Co-authored-by: shenlong-tanwen <139912620+shalong-tanwen@users.noreply.github.com>
Co-authored-by: Alex <alex.tran1502@gmail.com>

mobile/analysis_options.yaml

@@ -81,6 +81,7 @@ custom_lint:
         # acceptable exceptions for the time being (until Isar is fully replaced)
         - lib/providers/app_life_cycle.provider.dart
         - integration_test/test_utils/general_helper.dart
+        - lib/domain/services/background_worker.service.dart
         - lib/main.dart
         - lib/pages/album/album_asset_selection.page.dart
         - lib/routing/router.dart