fix(ui): 修复价格尾零、增加币种下拉框，并重构持仓引擎实现原币种/本位币双轨制盈亏计算

app/dashboard/assets/page.tsx

@@ -10,6 +10,7 @@ import {
   TableHeader,
   TableRow,
 } from '@/components/ui/table';
+import Big from 'big.js';
 
 export default async function AssetsPage() {
   const assets = await getAssets();
@@ -53,14 +54,14 @@ export default async function AssetsPage() {
                   <TableCell className="font-medium">{asset.symbol}</TableCell>
                   <TableCell>{typeLabels[asset.type] || asset.type}</TableCell>
                   <TableCell>{asset.baseCurrency}</TableCell>
-                  <TableCell>{asset.latestPrice}</TableCell>
+                  <TableCell>{asset.latestPrice ? new Big(asset.latestPrice).toString() : '-'}</TableCell>
                   <TableCell>
                     {asset.createdAt
                       ? new Date(asset.createdAt).toLocaleString('zh-CN')
                       : '-'}
                   </TableCell>
                   <TableCell>
-                    <UpdatePriceDialog assetId={asset.id} currentPrice={asset.latestPrice || '0'} />
+                    <UpdatePriceDialog assetId={asset.id} currentPrice={asset.latestPrice ? new Big(asset.latestPrice).toString() : '0'} />
                   </TableCell>
                 </TableRow>
               ))

app/dashboard/page.tsx

@@ -90,21 +90,33 @@ export default async function DashboardPage() {
                       <span className="font-medium">{pos.baseCurrency}</span>
                     </div>
                     <div className="flex justify-between">
-                      <span className="text-muted-foreground">CNY 估值</span>
-                      <span className="font-medium text-green-600">
-                        ¥{formatAmount(pos.cnyValue)}
+                      <span className="text-muted-foreground">持仓成本 ({pos.baseCurrency})</span>
+                      <span className="font-medium">
+                        {formatAmount(pos.totalCostNative)}
                       </span>
                     </div>
-                    <div className="flex justify-between">
+                    {(() => {
+                      const posPnlNative = new Big(pos.pnlNative);
+                      const posPnlNativePositive = posPnlNative.gte(0);
+                      return (
+                        <div className="flex justify-between">
+                          <span className="text-muted-foreground">当前盈亏 ({pos.baseCurrency})</span>
+                          <span className={`font-semibold ${posPnlNativePositive ? 'text-green-500' : 'text-red-500'}`}>
+                            {posPnlNativePositive ? '+' : ''}{formatAmount(pos.pnlNative)}
+                          </span>
+                        </div>
+                      );
+                    })()}
+                    <div className="flex justify-between opacity-50">
                       <span className="text-muted-foreground">成本 (CNY)</span>
                       <span className="font-medium">
                         ¥{formatAmount(pos.totalCostCny)}
                       </span>
                     </div>
-                    <div className="flex justify-between">
-                      <span className="text-muted-foreground">盈亏</span>
+                    <div className="flex justify-between opacity-50">
+                      <span className="text-muted-foreground">盈亏 (CNY)</span>
                       <span className={`font-semibold ${posPnlPositive ? 'text-green-500' : 'text-red-500'}`}>
-                        {posPnlPositive ? '+' : ''}{formattedPosPnl}
+                        {posPnlPositive ? '+' : ''}{formatAmount(pos.pnlCny)}
                       </span>
                     </div>
                   </div>