fix(swap): 修复互换价格变动时盈亏计算错误

- 在后端计算逻辑中添加 longRatio 参数用于区分多空头寸类型
- 修改前端 JavaScript 代码中的盈亏计算公式，加入 longRatio 参与计算
- 更新单元测试，增加空头头寸价格上涨时亏损的测试用例
- 补充前端测试用例验证空头头寸计算逻辑的准确性
- 修复了空头头寸在价格上涨时显示盈利而非亏损的计算错误

UnitTestProject/Modules/SwapModule/FrontendCalcCharacterizationTest.cs

@@ -258,6 +258,31 @@ namespace YLErp.Modules.SwapModule
             AssertDecimalEqual(5355000m, result.FloatPnlSum, 0.01m, "income FloatPnlSum包含分红");
         }
 
+        [TestMethod]
+        public void 收取空头_价格上涨_应为亏损()
+        {
+            var input = new UnwindInput
+            {
+                Multiplier = 100,
+                PosiGrossPrice = 1.01654321m,
+                TradingAmountAvg = 101.754321m,
+                PositionQty = 50000000m,
+                ContractSize = 1m,
+                CloseNotionalValue = 50827160.5m,
+                CloseQty = 0m,
+                PayDirection = 1,
+                PositionType = 2,
+                TradingFee = "0",
+                TradingFeePending = "0",
+                DividendIn = "-90400"
+            };
+
+            var result = FrontendCalcReference.CalcIncome(input);
+
+            AssertDecimalEqual(-50000m, result.MarkClosePnl, 0.01m, "收取空头价格上涨=盯市亏损");
+            AssertDecimalEqual(-140400m, result.FloatPnlSum, 0.01m, "盯市亏损加分红");
+        }
+
         private static void AssertDecimalEqual(decimal expected, decimal actual, decimal tolerance, string message = "")
         {
             Assert.IsTrue(Math.Abs(expected - actual) <= tolerance,