fix(swap): 修复债券结息价差盈亏计算逻辑

- 将价差盈亏计算从使用CloseNotionalValue改为使用PositionQty和ContractSize
- 更新前端JavaScript代码中的计算公式，按持仓数量和合约乘数计算价差盈亏
- 在UnwindInput模型中添加PositionQty和ContractSize字段
- 修正后台计算服务中的数据映射逻辑
- 添加FC_009测试用例验证债券价差按数量计算的正确性
- 更新现有测试用例的输入参数以匹配新的计算方式

UnitTestProject/Modules/SwapModule/FrontendCalcCharacterizationTest.cs

@@ -156,9 +156,9 @@ namespace YLErp.Modules.SwapModule
 
         /// <summary>
         /// [FC_006] 结息-债券多头-全量结算（基线）
-        /// income 用 CloseNotionalValue 而非 CloseQty，无 longRatio
-        /// EntryPrice=1.02, TradingAmountAvg=105(×100形态), CloseNotionalValue=10000
-        /// MarkClosePnl = 10000×(105×0.01−1.02)×1 = 10000×0.03 = 300
+        /// income 使用持仓数量和合约乘数，无 longRatio
+        /// EntryPrice=1.02, TradingAmountAvg=105(×100形态), PositionQty=10000, ContractSize=1
+        /// MarkClosePnl = 10000×1×(105×0.01−1.02)×1 = 10000×0.03 = 300
         /// </summary>
         [TestMethod]
         public void FC_006_结息_债券多头_全量结算()
@@ -166,7 +166,9 @@ namespace YLErp.Modules.SwapModule
             var input = new UnwindInput
             {
                 Multiplier = 100, PosiGrossPrice = 1.02m, TradingAmountAvg = 105m,
-                CloseNotionalValue = 10000, // income 用名义本金
+                PositionQty = 10000,
+                ContractSize = 1,
+                CloseNotionalValue = 10200, // 与数量刻意不同，守卫 income 不再误用名义本金
                 CloseQty = 0, // income 不用数量
                 PayDirection = 1, PositionType = 1,
                 TradingFee = "0", TradingFeePending = "0", DividendIn = "0"
@@ -188,7 +190,8 @@ namespace YLErp.Modules.SwapModule
             var input = new UnwindInput
             {
                 Multiplier = 100, PosiGrossPrice = 1.02m, TradingAmountAvg = 110m,
-                CloseNotionalValue = 10000, CloseQty = 0,
+                PositionQty = 10000, ContractSize = 1,
+                CloseNotionalValue = 10200, CloseQty = 0,
                 PayDirection = 1, PositionType = 1,
                 TradingFee = "0", TradingFeePending = "0", DividendIn = "0"
             };
@@ -209,7 +212,8 @@ namespace YLErp.Modules.SwapModule
             var input = new UnwindInput
             {
                 Multiplier = 100, PosiGrossPrice = 1.02m, TradingAmountAvg = 105m,
-                CloseNotionalValue = 10000, CloseQty = 0,
+                PositionQty = 10000, ContractSize = 1,
+                CloseNotionalValue = 10200, CloseQty = 0,
                 PayDirection = 1, PositionType = 1,
                 TradingFee = "0", TradingFeePending = "0", DividendIn = "0"
             };
@@ -225,6 +229,35 @@ namespace YLErp.Modules.SwapModule
             Console.WriteLine($"FC_008: SwapRealizedPnL={result.SwapRealizedPnL}, SwapMarginRebatePnl={result.SwapMarginRebatePnl} ✅");
         }
 
+        /// <summary>
+        /// [FC_009] 结息-债券支付端：价差盈亏必须按数量计算，不能按期初名义本金计算。
+        /// 纯价差 = 30000000×1×(80%−98%)×(−1) = 5400000；加分红-45000后合计5355000。
+        /// </summary>
+        [TestMethod]
+        public void FC_009_结息_债券价差按数量计算()
+        {
+            var input = new UnwindInput
+            {
+                Multiplier = 100,
+                PosiGrossPrice = 0.98m,
+                TradingAmountAvg = 80m,
+                PositionQty = 30000000m,
+                ContractSize = 1m,
+                CloseNotionalValue = 29400000m,
+                CloseQty = 0m,
+                PayDirection = 2,
+                PositionType = 1,
+                TradingFee = "0",
+                TradingFeePending = "0",
+                DividendIn = "-45000"
+            };
+
+            var result = FrontendCalcReference.CalcIncome(input);
+
+            AssertDecimalEqual(5400000m, result.MarkClosePnl, 0.01m, "income MarkClosePnl按数量计算");
+            AssertDecimalEqual(5355000m, result.FloatPnlSum, 0.01m, "income FloatPnlSum包含分红");
+        }
+
         private static void AssertDecimalEqual(decimal expected, decimal actual, decimal tolerance, string message = "")
         {
             Assert.IsTrue(Math.Abs(expected - actual) <= tolerance,