Phase 2: customers paying in coin (CRC/CRT/CRA/PSC), taint from stolen goods

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

src/Decentralized/Session.cs

@@ -28,6 +28,8 @@ namespace Decentralized
         public List<MarketEvent> ActiveEvents = new List<MarketEvent>();
         public NightReport LastNight;
         public bool OpeningNewsShown;
+        /// <summary>当天用币付款的成交额（信用点），夜间清零。</summary>
+        public double CoinSalesToday;
     }
 
     /// <summary>当前这一局的状态：读档 / 新游戏时载入，睡觉结算后写回。</summary>