add duration discard to fill attempts (#1301)

ErsatzTV.Core/Scheduling/CustomOrderCollectionEnumerator.cs

@@ -1,4 +1,5 @@
 using ErsatzTV.Core.Domain;
+using ErsatzTV.Core.Extensions;
 using ErsatzTV.Core.Interfaces.Scheduling;
 
 namespace ErsatzTV.Core.Scheduling;
@@ -6,6 +7,7 @@ namespace ErsatzTV.Core.Scheduling;
 public class CustomOrderCollectionEnumerator : IMediaCollectionEnumerator
 {
     private readonly IList<MediaItem> _sortedMediaItems;
+    private readonly Lazy<Option<TimeSpan>> _lazyMinimumDuration;
 
     public CustomOrderCollectionEnumerator(
         Collection collection,
@@ -17,6 +19,8 @@ public class CustomOrderCollectionEnumerator : IMediaCollectionEnumerator
             .OrderBy(ci => ci.CustomIndex)
             .Map(ci => mediaItems.First(mi => mi.Id == ci.MediaItemId))
             .ToList();
+        _lazyMinimumDuration = new Lazy<Option<TimeSpan>>(
+            () => _sortedMediaItems.Bind(i => i.GetDuration()).HeadOrNone());
 
         State = new CollectionEnumeratorState { Seed = state.Seed };
         while (State.Index < state.Index)
@@ -33,4 +37,6 @@ public class CustomOrderCollectionEnumerator : IMediaCollectionEnumerator
 
     public Option<MediaItem> Peek(int offset) =>
         throw new NotSupportedException();
+    
+    public Option<TimeSpan> MinimumDuration => _lazyMinimumDuration.Value;
 }