feat(job): D2 全市场选股 Job 化（kind=selection 异步）

- Job kind=selection：executor 分支用 SelectionService（spec=SelectionQuery），结果
  落 result_json、自动归档 Experiment（summary：as_of + 选出 N）；/api/jobs 与
  /api/experiments 的 result 解码支持 SelectionResult
- POST /api/selections/jobs：提交 SelectionQuery 为异步 Job（BackgroundTasks/subprocess）
- Web 选股页新增「异步（全市场）」按钮：提交 Job → waitJob 轮询结果（解决同步 60s+）
- tests/test_selection_job.py：executor 执行归档（SelectionResult/Experiment kind）、
  API 提交→轮询→结果与实验列表；全量 pytest + tsc 通过

frontend/web/app/selection/page.tsx

@@ -6,6 +6,7 @@
  */
 import { useEffect, useState } from "react";
 import { apiGet, apiPost } from "@/lib/api";
+import { waitJob } from "@/lib/jobs";
 import type {
   FactorMeta,
   SelectionCondition,
@@ -53,6 +54,7 @@ export default function SelectionPage() {
   const [result, setResult] = useState<SelectionResult | null>(null);
   const [selectionId, setSelectionId] = useState("");
   const [running, setRunning] = useState(false);
+  const [asyncBusy, setAsyncBusy] = useState(false);
   const [error, setError] = useState("");
   const [history, setHistory] = useState<SelectionMeta[] | null>(null);
 
@@ -111,6 +113,28 @@ export default function SelectionPage() {
     }
   }
 
+  /** 异步（全市场等长任务）：提交 Job 后台执行并轮询（解决同步 60s+）。 */
+  async function runAsync() {
+    setAsyncBusy(true);
+    setError("");
+    setResult(null);
+    try {
+      const { job_id } = await apiPost<{ job_id: string }>("/selections/jobs", buildQuery());
+      const out = await waitJob<SelectionResult>(job_id);
+      if (out.status === "success" && out.result) {
+        setSelectionId(job_id);
+        setResult(out.result);
+        apiGet<SelectionMeta[]>("/selections?limit=8").then(setHistory).catch(() => undefined);
+      } else {
+        setError(`任务${out.status}${out.error ? `：${out.error}` : ""}`);
+      }
+    } catch (e) {
+      setError((e as Error).message);
+    } finally {
+      setAsyncBusy(false);
+    }
+  }
+
   async function openHistory(id: string) {
     setError("");
     try {
@@ -279,9 +303,12 @@ export default function SelectionPage() {
         )}
 
         <div style={{ marginTop: 14 }}>
-          <Btn variant="primary" icon="play" loading={running} disabled={running} onClick={run}>
+          <Btn variant="primary" icon="play" loading={running} disabled={running || asyncBusy} onClick={run}>
             {running ? "筛选中…" : "执行选股"}
           </Btn>
+          <Btn variant="ghost" icon="clock" loading={asyncBusy} disabled={running || asyncBusy} onClick={runAsync}>
+            {asyncBusy ? "后台执行中…" : "异步（全市场）"}
+          </Btn>
         </div>
         {error ? (
           <div style={{ marginTop: 12 }}>