fix(退款): 修复创建退款申请插入审批尝试记录失败

创建路径把审批尝试记录在事务外预构造后原样插入，缺失只能在事务内生成的
attempt_no 与 package_usage_snapshot，触发 NOT NULL 与 CHECK 约束，
接口统一返回 2002 数据库错误（5xx 脱敏掩盖了具体消息）。

- 尝试记录收敛为事务内唯一构造点 buildAttempt，CreateCommand 与
  ResubmitCommand 只传按冻结商户派生的渠道退款请求号
- TriggerHistorical 补上缺失的尝试记录插入，此前 attempt.ID 恒为 0，
  必然以「关联已变化」冲突收场
- 按「首次接入企业微信审批的实例」语义回写
  tb_refund_request.approval_instance_id，恢复本地人工终审的 IS NULL
  防重保护与退款导出投影

internal/service/refund/service.go

@@ -200,9 +200,9 @@ func (s *Service) Create(ctx context.Context, req *dto.CreateRefundRequest) (*dt
 	if s.refundApprovalCreation == nil {
 		return nil, errors.New(errors.CodeServiceUnavailable, "退款审批能力未配置")
 	}
-	attempt := buildAttemptFromDecision(decision, refund, decision.ChannelConfig, time.Now())
 	result, err := s.refundApprovalCreation.Execute(ctx, refundapprovalapp.CreateCommand{
-		Refund: refund, Order: order, SubmitterAccountID: userID, Attempt: attempt,
+		Refund: refund, Order: order, SubmitterAccountID: userID,
+		ChannelRefundRequestNo: buildChannelRefundRequestNo(refund.Method, decision.ChannelConfig),
 	})
 	if err != nil {
 		failedRefund := *refund
@@ -852,12 +852,12 @@ func (s *Service) Resubmit(ctx context.Context, id uint, req *dto.ResubmitRefund
 	updated.CustomerAccountInfo = customerAccountInfo
 	updated.Creator = userID
 
-	attempt := buildAttemptFromDecision(decision, &updated, decision.ChannelConfig, time.Now())
+	attemptChannelRefundRequestNo := buildChannelRefundRequestNo(method, decision.ChannelConfig)
 	if s.refundApprovalCreation == nil {
 		return errors.New(errors.CodeServiceUnavailable, "退款审批能力未配置")
 	}
 	if _, err := s.refundApprovalCreation.Resubmit(ctx, id, refundapprovalapp.ResubmitCommand{
-		Refund: &updated, Attempt: attempt,
+		Refund: &updated, ChannelRefundRequestNo: attemptChannelRefundRequestNo,
 	}); err != nil {
 		s.recordRefundFailure(ctx, constants.AuditActionRefundResubmitted, "重新提交退款申请失败", refund, order, err)
 		return err