feat(portfolio): 支持显示已清仓历史持仓，增加防乱码 CSV 导出功能

app/dashboard/page.tsx

@@ -31,7 +31,7 @@ import { AddTransactionDialog } from '@/components/transactions/add-transaction-
 import { UpdateTransactionDialog } from '@/components/transactions/update-transaction-dialog';
 import { deleteTransaction } from '@/actions/transaction';
 import { importHistoricalPrices } from '@/actions/market';
-import { ChevronDown, ChevronUp, Plus, Edit3, Trash2, Upload } from 'lucide-react';
+import { ChevronDown, ChevronUp, Plus, Edit3, Trash2, Upload, Download, Eye } from 'lucide-react';
 import Big from 'big.js';
 
 const txTypeMap: Record<string, string> = {
@@ -55,6 +55,36 @@ function formatNative(value: string, baseCurrency: string): string {
   return `${symbol}${formatted}`;
 }
 
+function exportToCSV(positions: any[]) {
+  const headers = ["资产名称", "代码", "持仓量", "成本价", "现价", "总市值", "浮动盈亏", "累计盈亏"];
+
+  const rows = positions.map(item => [
+    item.name || item.symbol,
+    item.symbol,
+    item.quantity || '0',
+    new Big(item.avgCostNative || '0').toFixed(2),
+    item.latestPrice || '0',
+    new Big(item.marketValueNative || '0').toFixed(2),
+    new Big(item.floatingPnlNative || '0').toFixed(2),
+    new Big(item.cumulativePnlNative || '0').toFixed(2),
+  ]);
+
+  const csvContent = [
+    headers.join(","),
+    ...rows.map(e => e.map(val => `"${val}"`).join(","))
+  ].join("\n");
+
+  const blob = new Blob(["\uFEFF" + csvContent], { type: 'text/csv;charset=utf-8;' });
+  const url = URL.createObjectURL(blob);
+  const link = document.createElement("a");
+  link.setAttribute("href", url);
+  link.setAttribute("download", `portfolio_details_${new Date().toISOString().split('T')[0]}.csv`);
+  document.body.appendChild(link);
+  link.click();
+  document.body.removeChild(link);
+  URL.revokeObjectURL(url);
+}
+
 function formatPnl(value: string, percent: string, baseCurrency: string): { text: string; className: string } {
   const isPositive = new Big(value).gte(0);
   const symbol = getCurrencySymbol(baseCurrency);
@@ -91,11 +121,21 @@ export default function DashboardPage() {
   const [importDialogOpen, setImportDialogOpen] = useState(false);
   const [importAssetId, setImportAssetId] = useState<string>('');
   const [importText, setImportText] = useState('');
+  const [showCleared, setShowCleared] = useState(false);
+  const [positionsRaw, setPositionsRaw] = useState<any[]>([]);
+
+  useEffect(() => {
+    const filtered = showCleared
+      ? positionsRaw
+      : positionsRaw.filter(pos => new Big(pos.quantity || '0').gt('1e-8'));
+    setPositions(filtered);
+  }, [showCleared, positionsRaw]);
 
   useEffect(() => {
     async function loadData() {
-      const summary = await getPortfolioSummary();
+      const summary = await getPortfolioSummary(true);
       const allAssets = await getAssets();
+      setPositionsRaw(summary.positions);
       setPositions(summary.positions);
       setTotalCnyValue(summary.totalCnyValue);
       setTotalPnlCny(summary.totalPnlCny);
@@ -271,8 +311,29 @@ export default function DashboardPage() {
       </Card>
 
       <Card>
-        <CardHeader>
+        <CardHeader className="flex flex-row items-center justify-between space-y-0">
           <CardTitle>持仓明细</CardTitle>
+          <div className="flex items-center gap-3">
+            <label className="flex items-center gap-2 cursor-pointer text-sm text-muted-foreground hover:text-foreground transition-colors">
+              <input
+                type="checkbox"
+                checked={showCleared}
+                onChange={(e) => setShowCleared(e.target.checked)}
+                className="h-4 w-4 rounded border-border text-primary focus:ring-primary cursor-pointer"
+              />
+              <Eye className="h-4 w-4" />
+              显示历史持仓
+            </label>
+            <Button
+              size="sm"
+              variant="outline"
+              onClick={() => exportToCSV(positions)}
+              disabled={positions.length === 0}
+            >
+              <Download className="h-4 w-4 mr-1" />
+              导出 CSV
+            </Button>
+          </div>
         </CardHeader>
         <CardContent>
           {positions.length === 0 ? (