FF-1602: Added bitrate per channel to add audio track

VideoNodes/Tests/_LocalFileService.cs

@@ -365,6 +365,11 @@ public class LocalFileService : IFileService
         }
     }
 
+    public Result<long> DirectorySize(string path)
+    {
+        throw new NotImplementedException();
+    }
+
     public Result<bool> SetCreationTimeUtc(string path, DateTime date)
     {
         if (IsProtectedPath(ref path))