采购提交与报销新建/提交事务显式使用10秒上限 [09-27-purchase-submit-tx-timeout]

负载下采购提交事务超过 Prisma 交互事务默认 5000ms（P2028）返回 500。
分段计时显示无单一瓶颈（总时长中位 843ms、最大 3506ms，编号锁等待
最多 535ms），是约 20 条顺序查询整体变慢贴近上限。报销新建/提交同结构。
三处改用项目既有的 { maxWait: 5000, timeout: 10000 }，事务内容不变；
新增采购与报销提交的事务选项回归断言。

Co-Authored-By: Claude Opus 5.5 <[email protected]>

server/tests/unit/routes/purchase.submit-budget-precheck.test.js

@@ -315,6 +315,17 @@ describe("purchase request submit budget precheck gate", () => {
 
     await app.close();
   });
+
+  it("runs the submit transaction with a 10s budget instead of Prisma's 5s default", async () => {
+    resolveEntityPrecheckMock.mockResolvedValue(buildPrecheck({ budgetHint: { controlMode: "block" } }));
+    const { app, prisma } = await buildApp({ budgetControlMode: "warn", budgetPrecheckEnabled: false });
+
+    const response = await app.inject({ method: "POST", url: `/api/purchase-requests/${PURCHASE_REQUEST_ID}/submit` });
+
+    expect(response.statusCode).toBe(200);
+    expect(prisma.$transaction).toHaveBeenCalledWith(expect.any(Function), { maxWait: 5000, timeout: 10000 });
+    await app.close();
+  });
 });
 
 it.each([1, 2])("submits a stored v%s purchase draft under active policy without reclassifying it", async (version) => {