Stage 7.2: manipulation detection (player price push, prediction/perp forfeits)

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

tests/Decentralized.Domain.Tests/Program.cs

@@ -1239,6 +1239,34 @@ internal static class Program
             Check(PredictMath.EraProb(60, 62, 65, 58) > 0.5 && PredictMath.EraProb(60, 70, 71, 58) == 0, "预警后窗口覆盖区间就是高概率");
         });
 
+        Test("操纵检出：被查概率随推价幅度升高，推价每晚衰减，行情盘押中按方向被判", () =>
+        {
+            Check(Market.ManipChance(0.01) == 0 && Market.ManipChance(-0.01) == 0, "幅度低于免查线不查");
+            Check(Market.ManipChance(0.05) > Market.ManipChance(0.03) && Market.ManipChance(-0.05) == Market.ManipChance(0.05), "幅度越大越容易被查，方向无关");
+            Check(Market.ManipChance(5) == Tuning.ManipMax, "封顶");
+            var mk = Market.CreateDefault(5); double p0 = mk.Price;
+            mk.PlayerPush += Math.Log(1.1);
+            Check(Math.Abs(mk.NeutralPrice - p0 / 1.1 * 1.0) < 1e-6 || mk.NeutralPrice > 0, "没有玩家时的价格");
+            double before = mk.PlayerPush; mk.Night(new List<MarketEvent>(), new Rng(1), 5, a => 1);
+            Check(Math.Abs(mk.PlayerPush - before * (1 - Tuning.Revert)) < 1e-9, "推价随回归衰减");
+            // 行情盘：玩家推高后押「是」赢了，按概率被判操纵；押「否」不算；没推价不查
+            int manip = 0, win = 0, noPush = 0;
+            for (ulong sd = 1; sd <= 200; sd++)
+            {
+                foreach (var (yes, push, outcome) in new[] { (true, 0.06, true), (false, 0.06, false), (true, 0.0, true) })
+                {
+                    var bk = new PredictBook(); var w = new Wallet { Address = "w" }; w.Add(Assets.CRC, 1e5);
+                    var m = PredictMarket.Create(++bk.Seq, PredictKind.Price, "PSC", "PSC", 100, 4, 5, 5, 0.3); bk.Markets.Add(m);
+                    bk.Buy(w, m, yes, 510, 4, a => 1, false, out _);
+                    var ev = bk.Night(5, new string[0], x => outcome, _ => w, new Rng(sd), push);
+                    if (ev[0].Kind == "manip") { if (yes && push > 0) manip++; else Check(false, "不该被判操纵"); Check(ev[0].Fraud > 0, "记罪证"); Check(w.Get(Assets.CRC) < 1e5 - 400, "本金没收"); }
+                    else if (yes && push > 0) win++; else if (push == 0) noPush++;
+                }
+            }
+            double expect = Market.ManipChance(0.06) * 200;
+            Check(Math.Abs(manip - expect) < 40 && manip + win == 200 && noPush == 200, $"推价 6% 约 {expect:0} 次被判，被判 {manip}，没被判 {win}");
+        });
+
         Test("预测市场：先验概率", () =>
         {
             Check(Math.Abs(PredictMath.PurityAtLeast(8500, 8000, 8999) - 0.5) < 1e-9, "纯度 8500 以上一半");