fix(server,web,mobile): Incorrectly record and show timestamp and time zone of the asset (#706)

Implemented a mechanism to extract the correct time zone from the GPS coordinate if presented in the file's EXIF, and to convert the timestamp to the correct UTC time so that the time will show correctly based on the mobile/web local time zone.

mobile/lib/modules/backup/views/failed_backup_status_page.dart

@@ -90,7 +90,7 @@ class FailedBackupStatusPage extends HookConsumerWidget {
                                 DateFormat.yMMMMd('en_US').format(
                                   DateTime.parse(
                                     errorAsset.createdAt.toString(),
-                                  ),
+                                  ).toLocal(),
                                 ),
                                 style: TextStyle(
                                   fontSize: 12,