refactor: asset media endpoints (#9831)

* refactor: asset media endpoints

* refactor: mobile upload livePhoto as separate request

* refactor: change mobile backup flow to use new asset upload endpoints

* chore: format and analyze dart code

* feat: mark motion as hidden when linked

* feat: upload video portion of live photo before image portion

* fix: incorrect assetApi calls in mobile code

* fix: download asset

---------

Co-authored-by: shenlong-tanwen <139912620+shalong-tanwen@users.noreply.github.com>
Co-authored-by: Zack Pollard <zackpollard@ymail.com>

mobile/lib/widgets/search/explore_grid.dart

@@ -44,7 +44,7 @@ class ExploreGrid extends StatelessWidget {
         final content = curatedContent[index];
         final thumbnailRequestUrl = isPeople
             ? getFaceThumbnailUrl(content.id)
-            : '${Store.get(StoreKey.serverEndpoint)}/asset/thumbnail/${content.id}';
+            : '${Store.get(StoreKey.serverEndpoint)}/assets/${content.id}/thumbnail';
 
         return ThumbnailWithInfo(
           imageUrl: thumbnailRequestUrl,