fix(pack): tutorial pack_open ThenIncludes OwnedItemEntry.Item

Without .ThenInclude(i => i.Item), the OwnedItemEntry.Item nav defaults to a
new ItemEntry() with Id=0 (project_ef_nav_include_pitfall), so the
FirstOrDefault(i => i.Item.Id == ticketItemId) lookup never matched. The
ticket was never decremented and reward_list omitted the post-state entry —
on the next /tutorial/pack_info the pack stayed visible and the client
re-clicked into plain /pack/open, which 501s on type_detail=5.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

SVSim.UnitTests/Controllers/TutorialFlowEndToEndTests.cs

@@ -103,6 +103,11 @@ public class TutorialFlowEndToEndTests
 
         Assert.That(await factory.GetViewerTutorialStateAsync(viewerId), Is.EqualTo(100),
             "Viewer reaches TUTORIAL_END after the full flow.");
+
+        // The gift granted item 90001 count=1 (via /tutorial/gift_receive entry 71478630).
+        // /tutorial/pack_open consumes it; assert the ticket is gone post-flow.
+        Assert.That(await factory.GetOwnedItemCountAsync(viewerId, 90001), Is.EqualTo(0),
+            "Starter legendary ticket must be consumed by /tutorial/pack_open.");
     }
 
     private static Task<HttpResponseMessage> Post(HttpClient client, string url, string body)