feat(web): M8.6b 回测页做实 + 首页入口更新（零新后端 API）

- backtest 页：成本参数表单（手续费/印花税/滑点 %）+ 初始资金 → ResearchSpec.costs/
  initial_capital；结果新增年度收益卡与成交明细表（买/卖日、买/卖价、收益、累计换手）
- Dashboard 入口卡加入「股票筛选」「交易信号」（6 张）
- lib/types.ts：ResearchSpec 增加 price_adjustment/costs/portfolio/initial_capital，
  Trade 补 entry_price/exit_price
- 页面 200 冒烟 + tsc --noEmit 通过

frontend/web/app/backtest/page.tsx

@@ -28,6 +28,10 @@ export default function BacktestPage() {
   const [start, setStart] = useState("");
   const [end, setEnd] = useState("");
   const [excludeSt, setExcludeSt] = useState(true);
+  const [commission, setCommission] = useState(0.03); // %
+  const [stamp, setStamp] = useState(0.05);
+  const [slippage, setSlippage] = useState(0.1);
+  const [capital, setCapital] = useState(1_000_000);
   const [result, setResult] = useState<BacktestResult | null>(null);
   const [running, setRunning] = useState(false);
   const [jobId, setJobId] = useState("");
@@ -65,6 +69,12 @@ export default function BacktestPage() {
         factors: [{ name: factor, weight: 1 }],
         selection: { top_n: topN },
         rebalance,
+        costs: {
+          commission_rate: commission / 100,
+          stamp_tax_rate: stamp / 100,
+          slippage_rate: slippage / 100,
+        },
+        initial_capital: capital,
         period: [start, end],
       };
       // 异步 Job：后台执行（全市场可能数十秒），轮询到终态
@@ -133,6 +143,22 @@ export default function BacktestPage() {
               <option value="weekly">周度</option>
             </select>
           </Field>
+          <Field label="手续费率 %">
+            <input className="input" type="number" step="0.01" min={0} value={commission}
+              onChange={(e) => setCommission(Number(e.target.value))} />
+          </Field>
+          <Field label="印花税率 %">
+            <input className="input" type="number" step="0.01" min={0} value={stamp}
+              onChange={(e) => setStamp(Number(e.target.value))} />
+          </Field>
+          <Field label="滑点率 %">
+            <input className="input" type="number" step="0.01" min={0} value={slippage}
+              onChange={(e) => setSlippage(Number(e.target.value))} />
+          </Field>
+          <Field label="初始资金（元）">
+            <input className="input" type="number" step={100000} min={10000} value={capital}
+              onChange={(e) => setCapital(Number(e.target.value))} />
+          </Field>
           <Field label="开始日期">
             <input type="date" className="input" value={start} onChange={(e) => setStart(e.target.value)} />
           </Field>
@@ -228,6 +254,58 @@ function ResultView({ result }: { result: BacktestResult }) {
         )}
       </Card>
 
+      {result.yearly_returns.length ? (
+        <Card icon="calendar" title="年度收益（%）" tools={<Pill>均值 {(result.yearly_returns.reduce((a, y) => a + y.return_pct, 0) / result.yearly_returns.length).toFixed(2)}%</Pill>}>
+          <div className="chips">
+            {result.yearly_returns.map((y) => (
+              <span className="chip" key={y.year}>
+                <b>{y.year}</b>
+                <span className={y.return_pct >= 0 ? "tone-pos" : "tone-neg"}>
+                  {y.return_pct.toFixed(2)}%
+                </span>
+              </span>
+            ))}
+          </div>
+        </Card>
+      ) : null}
+
+      {result.trades.length ? (
+        <Card
+          icon="scale"
+          title={`成交明细 · ${result.trades.length} 笔`}
+          tools={<Pill>{result.turnover_pct.toFixed(2)}% 累计换手</Pill>}
+        >
+          <div className="table-wrap">
+            <table className="tbl">
+              <thead>
+                <tr>
+                  <th>买入日</th>
+                  <th>卖出日</th>
+                  <th>代码</th>
+                  <th>买价</th>
+                  <th>卖价</th>
+                  <th>收益</th>
+                </tr>
+              </thead>
+              <tbody>
+                {result.trades.map((t) => (
+                  <tr key={`${t.symbol}-${t.entry_date}-${t.exit_date}`}>
+                    <td className="mono dim">{t.entry_date}</td>
+                    <td className="mono dim">{t.exit_date}</td>
+                    <td className="mono"><b>{t.symbol}</b></td>
+                    <td className="mono">{t.entry_price?.toFixed(2) ?? "-"}</td>
+                    <td className="mono">{t.exit_price?.toFixed(2) ?? "-"}</td>
+                    <td className={t.return_pct >= 0 ? "tone-pos" : "tone-neg"}>
+                      {t.return_pct.toFixed(2)}%
+                    </td>
+                  </tr>
+                ))}
+              </tbody>
+            </table>
+          </div>
+        </Card>
+      ) : null}
+
       <UnimplementedNote items={result.unimplemented} />
     </>
   );