Stage 9.2: mixer operator Tumbler storyline with key drive item

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

src/Decentralized.Domain/Mixer.cs

@@ -44,7 +44,10 @@ namespace Decentralized.Domain
         public bool RecentlyMixed(int day) => day - LastReturnDay <= Tuning.AmlWindowDays;
 
         /// <summary>一轮的清洗率：基准 × 匿名集系数。</summary>
-        public static double RoundRate(double depositValue) => Tuning.MixerCleanRate * Tuning.MixerNpcVolume / (Tuning.MixerNpcVolume + Math.Max(0, depositValue));
+        /// <summary>每轮手续费（剧情可能改动）。</summary>
+        public static double Fee => Math.Min(0.5, Tuning.MixerFee * StoryMods.Current.MixerFee);
+
+        public static double RoundRate(double depositValue) => Tuning.MixerCleanRate * Tuning.MixerNpcVolume * StoryMods.Current.MixerVolume / (Tuning.MixerNpcVolume * StoryMods.Current.MixerVolume + Math.Max(0, depositValue));
 
         /// <summary>存入：从钱包按价值比例带走污点与成本。轮数超出范围或余额不足返回 null。</summary>
         public MixDeposit Deposit(Wallet w, string asset, double amount, int rounds, int day, Func<string, double> price)
@@ -78,7 +81,7 @@ namespace Decentralized.Domain
             var results = new List<MixResult>();
             foreach (var d in Pending.ToList())
             {
-                if (rng.Chance(Tuning.MixerRugChance))
+                if (rng.Chance(Math.Min(1, Tuning.MixerRugChance * StoryMods.Current.MixerRug)))
                 {
                     Pending.Remove(d);
                     results.Add(new MixResult { Rugged = true, Asset = d.Asset, Amount = d.Amount });
@@ -88,7 +91,7 @@ namespace Decentralized.Domain
                 Pending.Remove(d);
                 double rate = RoundRate(d.Amount * price(d.Asset));
                 double taint = d.Taint * Math.Pow(1 - rate, d.Rounds);
-                double amount = d.Amount * Math.Pow(1 - Tuning.MixerFee, d.Rounds);
+                double amount = d.Amount * Math.Pow(1 - Fee, d.Rounds);
                 bool flagged = Sanctioned(day);
                 var w = wallet(d.Wallet);
                 w.Add(d.Asset, amount);