Flagged status follows traceable transfers; wallet split review

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

src/Decentralized.Domain/Wallet.cs

@@ -111,7 +111,8 @@ namespace Decentralized.Domain
         public double Value(Func<string, double> price) => Balances.Sum(kv => kv.Value * price(kv.Key));
 
         /// <summary>
-        /// 转出：taint 和 basis 按转出价值占地址总价值的比例带走。Ponero 等不可追踪资产转入时，污点不随之进入目标地址。
+        /// 转出：taint 和 basis 按转出价值占地址总价值的比例带走；被标记的地址转出可追踪的币，收款地址也被标记。
+        /// Ponero 等不可追踪资产转入时，污点和标记都不随之进入目标地址。
         /// </summary>
         public static void Transfer(Wallet from, Wallet to, string asset, double amount, Func<string, double> price)
         {
@@ -124,7 +125,7 @@ namespace Decentralized.Domain
             from.Basis -= basis;
             to.Add(asset, amount);
             var spec = Assets.Get(asset);
-            if (spec == null || spec.Traceable) to.Taint += taint;
+            if (spec == null || spec.Traceable) { to.Taint += taint; if (from.Flagged) to.Flagged = true; }
             to.Basis += basis;
         }
     }