Stage 4: black market orders, escrow, delivery, seller scams, platform rug

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

src/Decentralized.Domain/BlackMarket.cs

@@ -18,7 +18,7 @@ namespace Decentralized.Domain
     /// 付出去的币连同按比例的污点一起留在卖家那边；Ponero 兑换处把任意币兑成无法追踪的 Ponero（污点留在原地），有每日额度和手续费。
     /// 镇压期间整个平台下线。
     /// </summary>
-    public sealed class BlackMarket
+    public sealed partial class BlackMarket
     {
         public List<BmOffer> Offers = new List<BmOffer>();
         public int RefreshedDay = -999;