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。

server/tests/unit/routes/ai.test.js

@@ -318,3 +318,7 @@ describe("AI routes", () => {
     await outsiderApp.close();
   });
 });
+
+describe("AI target input reasons", () => {
+  it.each([["reimbursements", "ai.reimbursement_id_invalid"], ["purchase-requests", "ai.purchase_id_invalid"], ["assets", "ai.asset_id_invalid"]])("rejects invalid %s id before DB/provider", async (path, reasonCode) => { const prisma = buildPrisma(); const app = await buildTestApp({ prisma, employee: { id: "synthetic", permissionCodes: ["ai.assist"] }, config: { aiProvider: "mock" } }); try { const r = await app.inject({ method: "POST", url: `/api/ai/suggestions/${path}/bad`, headers: { authorization: "Bearer synthetic" }, payload: {} }); expect(r.statusCode).toBe(400); expect(r.json().error.details.reasonCode).toBe(reasonCode); for (const model of Object.values(prisma)) for (const fn of Object.values(model)) expect(fn).not.toHaveBeenCalled(); } finally { await app.close(); } });
+});