🐛 Fix message attachment did not marked

DysonNetwork.Sphere/Storage/Handlers/MessageReadReceiptFlushHandler.cs

@@ -10,10 +10,12 @@ public class MessageReadReceiptFlushHandler(IServiceProvider serviceProvider) :
 {
     public async Task FlushAsync(IReadOnlyList<MessageReadReceipt> items)
     {
+        var distinctItems = items.DistinctBy(x => new { x.MessageId, x.SenderId }).ToList();
+
         using var scope = serviceProvider.CreateScope();
         var db = scope.ServiceProvider.GetRequiredService<AppDatabase>();
 
-        await db.BulkInsertAsync(items);
+        await db.BulkInsertAsync(distinctItems);
     }
 }