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/src/services/paymentOrderXls.js

@@ -109,7 +109,9 @@ function buildPaymentOrderRows(config, batch) {
       addBlocker(error.code ?? "payee_account_unavailable", entityCodeHint);
     }
     try {
-      payeeName = requiredText(payee?.name, "payee_name_missing");
+      payeeName = batch.entity_type === "loan_repayment"
+        ? decryptRequired(config, payee?.accountNameEncrypted, "payee_name_missing")
+        : requiredText(payee?.name, "payee_name_missing");
     } catch (error) {
       addBlocker(error.code ?? "payee_name_missing", entityCodeHint);
     }
@@ -155,8 +157,8 @@ function buildPaymentOrderRows(config, batch) {
       "",
       serial,
       Number(amount.toFixed(2)),
-      "报销款",
-      `报销款 ${entityCode}`,
+      batch.entity_type === "loan_repayment" ? "还款" : "报销款",
+      batch.entity_type === "loan_repayment" ? "归还借款本金" : `报销款 ${entityCode}`,
       "0",
       "",
       "",