fix(ledger): 修复 T+0 时间戳碰撞导致聚合乱序，实装清仓归零阻断机制

src/actions/portfolio.ts

@@ -194,7 +194,7 @@ export async function getPortfolioPositions(includeCleared: boolean = false): Pr
     })
     .from(transactions)
     .leftJoin(assets, eq(assets.id, transactions.assetId))
-    .orderBy(asc(transactions.executedAt));
+    .orderBy(asc(transactions.executedAt), asc(transactions.createdAt), asc(transactions.id));
 
   const dynamicRateMap = await getLatestRatesMap();
 
@@ -232,6 +232,11 @@ export async function getPortfolioPositions(includeCleared: boolean = false): Pr
   for (const tx of allTransactions) {
     if (!tx.assetId) continue;
 
+    // [架构红线] 强制标准化交易类型：大写 + 去空格，兼容中文脏数据
+    const txType = String(tx.txType).toUpperCase().trim();
+    const isBuy = txType === 'BUY' || txType === '\u5165\u4e70';
+    const isSell = txType === 'SELL' || txType === '\u5356\u51fa';
+
     const existing = holdings.get(tx.assetId);
     if (!existing) {
       holdings.set(tx.assetId, {
@@ -257,7 +262,7 @@ export async function getPortfolioPositions(includeCleared: boolean = false): Pr
 
     const holding = holdings.get(tx.assetId)!;
 
-    if (tx.txType === 'BUY') {
+    if (isBuy) {
       holding.quantity = holding.quantity.plus(new Big(tx.quantity));
       const costPerUnit = new Big(tx.quantity).times(new Big(tx.price));
       holding.totalBuyCostNative = holding.totalBuyCostNative.plus(costPerUnit);
@@ -276,7 +281,7 @@ export async function getPortfolioPositions(includeCleared: boolean = false): Pr
       if (!holding.firstBuyDate && tx.executedAt) {
         holding.firstBuyDate = new Date(tx.executedAt);
       }
-    } else if (tx.txType === 'SELL') {
+    } else if (isSell) {
       // 计算卖出时的平均成本 (Native)
       let avgCostPerUnitNative = new Big('0');
       if (holding.totalBuyQuantity.gt(0)) {
@@ -307,9 +312,17 @@ export async function getPortfolioPositions(includeCleared: boolean = false): Pr
       holding.realizedPnlCny = holding.realizedPnlCny.plus(realizedPnlCny);
 
       holding.quantity = holding.quantity.minus(new Big(tx.quantity));
-    } else if (tx.txType === 'AIRDROP') {
+
+      // [核心阻断器] 防浮点数灰尘与清仓重置：一旦清仓，强制清零所有持仓成本
+      if (holding.quantity.lte(new Big('1e-8'))) {
+        holding.quantity = new Big(0);
+        holding.totalBuyCostCny = new Big(0);
+        holding.totalBuyCostNative = new Big(0);
+        holding.totalBuyQuantity = new Big(0);
+      }
+    } else if (txType === 'AIRDROP') {
       holding.quantity = holding.quantity.plus(new Big(tx.quantity));
-    } else if (tx.txType === 'DIVIDEND') {
+    } else if (txType === 'DIVIDEND') {
       const dividendAmountNative = new Big(tx.quantity).times(new Big(tx.price));
       const dividendCny = dividendAmountNative.times(new Big(tx.exchangeRate || '1'));
       holding.accumulatedDividendsCny = holding.accumulatedDividendsCny.plus(dividendCny);