feat(deposits): add refund rejection path with reason

apps/server/src/deposits/deposits.service.ts

@@ -158,6 +158,21 @@ export class DepositsService {
 
     return this.repo.save(deposit);
   }
+
+  async rejectRefund(id: number, reason: string, userId: number) {
+    const deposit = await this.repo.findOne({ where: { id } });
+    if (!deposit) throw new NotFoundException('押金记录不存在');
+
+    if (!deposit.refundStatus || deposit.refundStatus === 'refunded') {
+      throw new BadRequestException('未找到待审批的退款申请');
+    }
+
+    deposit.refundStatus = null;
+    deposit.refundApprovedBy = userId;
+    deposit.refundApprovedAt = new Date();
+    deposit.refundRejectedReason = reason;
+    return this.repo.save(deposit);
+  }
   async findPendingRefunds() {
     const baseWhere = await this.scope.filter({});
     return this.repo.find({