refactor(ui): 重塑 Dashboard 数据流，剔除违规本金反推逻辑，应用顺向盈亏计算

src/actions/portfolio.ts

@@ -468,11 +468,13 @@ export async function getPortfolioSummary(includeCleared: boolean = false) {
   let totalCnyValue = new Big('0');
   let totalPnlCny = new Big('0');
   let totalFloatingPnlCny = new Big('0');
+  let totalCostCny = new Big('0');
 
   for (const pos of positions) {
     totalCnyValue = totalCnyValue.plus(new Big(pos.marketValueCny || '0'));
     totalPnlCny = totalPnlCny.plus(new Big(pos.accumulatedPnlCny || '0'));
     totalFloatingPnlCny = totalFloatingPnlCny.plus(new Big(pos.floatingPnlCny || '0'));
+    totalCostCny = totalCostCny.plus(new Big(pos.totalCostCny || '0'));
   }
 
   const chartData = positions.map((pos, index) => ({
@@ -531,6 +533,7 @@ export async function getPortfolioSummary(includeCleared: boolean = false) {
   return {
     positions,
     totalCnyValue: totalCnyValue.toString(),
+    totalCostCny: totalCostCny.toString(),
     totalPnlCny: totalPnlCny.toString(),
     unrealizedPnlCny: totalFloatingPnlCny.toString(),
     chartData,