Omit BoxSet related materialization

MediaBrowser.Controller/Persistence/IItemQueryHelpers.cs

@@ -78,6 +78,19 @@ public interface IItemQueryHelpers
         InternalItemsQuery filter,
         Guid ancestorId);
 
+    /// <summary>
+    /// Builds an <see cref="IQueryable{Guid}"/> of folder IDs whose descendants are all played
+    /// for the given user. Composable into outer queries to avoid an extra DB roundtrip.
+    /// </summary>
+    /// <param name="context">The database context the resulting query is bound to.</param>
+    /// <param name="folderIds">A query yielding candidate folder IDs.</param>
+    /// <param name="user">The user for access filtering and played status.</param>
+    /// <returns>An <see cref="IQueryable{Guid}"/> of fully-played folder IDs.</returns>
+    IQueryable<Guid> GetFullyPlayedFolderIdsQuery(
+        JellyfinDbContext context,
+        IQueryable<Guid> folderIds,
+        User user);
+
     /// <summary>
     /// Deserializes a <see cref="BaseItemEntity"/> into a <see cref="BaseItem"/>.
     /// </summary>