chore(mobile): clean up (#3256)

mobile/lib/main.dart

@@ -93,7 +93,8 @@ Future<Isar> loadDb() async {
       DuplicatedAssetSchema,
       LoggerMessageSchema,
       ETagSchema,
-      Platform.isAndroid ? AndroidDeviceAssetSchema : IOSDeviceAssetSchema,
+      if (Platform.isAndroid) AndroidDeviceAssetSchema,
+      if (Platform.isIOS) IOSDeviceAssetSchema,
     ],
     directory: dir.path,
     maxSizeMiB: 256,