完善借款、编号、付款与预算并发及验收（09-06-release-gate-integrity）

汇总已落盘的借款本金与还款、兼容历史编号的周期化编号、付款责任与回单核验、报销进度和排序、PWA/采购事务、错误原因与日期校验及ERP退役。
统一共享预算池锁序和锁后判断，恢复差旅原预算选择，补原因码固定夹具及反向完整性检查。
纳入配套迁移、测试、受管QA、分层验收合同、规约及任务记录；原始证据留在ignored artifacts。

关联任务：09-17-company-loan-principal-repayment、09-17-erp-exclusive-retirement、09-18-reimbursement-periodic-numbering、09-08-reimbursement-payment-closeout、09-18-local-concurrency-product-fixes、09-19-budget-pool-concurrency、09-05-error-explainability-payment-readiness。
预算补审由Claude定向验证2文件928项通过，原4446/28及r6结果仍仅对应各自历史输入；本轮未重跑测试。
完整新候选门禁、R1真实入口接入与12项公网义务仍开放。生产编号未启用、差旅仍冻结；不推送、不部署，不宣称发布资格。

client/tests/e2e/procurement-flow.spec.ts

@@ -38,6 +38,7 @@ test("E2E 采购主链路：员工提单→经理审批→财务归档", async (
   );
   await page.getByTestId("purchase-requests-create").click();
   const createResponse = await createResponsePromise;
+  expect(createResponse.status(), "创建合成采购草稿").toBe(200);
   const createPayload = (await createResponse.json()) as {
     data: { purchaseRequest: { id: string } };
   };
@@ -62,12 +63,32 @@ test("E2E 采购主链路：员工提单→经理审批→财务归档", async (
   await page.locator('[data-testid^="purchase-item-unit-price-"]:visible').first().fill("100");
   await expect(page.getByTestId("purchase-budget-hint")).toContainText("未匹配预算池");
 
+  const saveResponsePromise = page.waitForResponse(
+    (response) => response.request().method() === "PATCH" && new URL(response.url()).pathname === `/api/purchase-requests/${purchaseRequestId}`,
+  );
+  const precheckResponsePromise = page.waitForResponse(
+    (response) => response.request().method() === "POST" && new URL(response.url()).pathname === `/api/purchase-requests/${purchaseRequestId}/precheck`,
+  );
   const submitResponsePromise = page.waitForResponse(
     (response) =>
       response.request().method() === "POST" &&
       new URL(response.url()).pathname === `/api/purchase-requests/${purchaseRequestId}/submit`,
   );
+  // Keep later listeners handled when an earlier stage fails; assertions still
+  // await the original promises and never turn rejection into success.
+  void precheckResponsePromise.catch(() => undefined);
+  void submitResponsePromise.catch(() => undefined);
   await page.getByTestId("purchase-submit").click();
+  const saved = await saveResponsePromise;
+  expect(saved.status(), "提交前保存合成采购草稿").toBe(200);
+  const prechecked = await precheckResponsePromise;
+  expect(prechecked.status(), "合成采购提交前校验").toBe(200);
+  const precheck = (await prechecked.json()).data as { decision: string };
+  expect(["pass", "warn", "manual_review"]).toContain(precheck.decision);
+  if (precheck.decision === "warn" || precheck.decision === "manual_review") {
+    await expect(page.getByTestId("action-confirm-dialog")).toBeVisible();
+    await page.getByTestId("action-confirm-submit").click();
+  }
   const submitResponse = await submitResponsePromise;
   if (!submitResponse.ok()) {
     const failureText = await submitResponse.text();