feature(mobile): Hardening synchronization mechanism + Pull to refresh (#2085)

* fix(mobile): allow syncing duplicate local IDs

* enable to run isar unit tests on CI

* serialize sync operations, add pull to refresh on timeline

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Co-authored-by: Fynn Petersen-Frey <zoodyy@users.noreply.github.com>

mobile/test/favorite_provider_test.dart

@@ -23,6 +23,7 @@ Asset _getTestAsset(int id, bool favorite) {
     updatedAt: DateTime.now(),
     isLocal: false,
     durationInSeconds: 0,
+    type: AssetType.image,
     fileName: '',
     isFavorite: favorite,
   );