优化支付退款钱包链路

backend/internal/modules/wallet/repository.go

@@ -117,6 +117,29 @@ func (r *Repository) ConfirmRechargeFromChannel(userID uint64, bizNo string, amo
 	})
 }
 
+// Withdraw 保留仓库能力；当前公开提现入口在 service 层标记为待开发，不会调用到这里。
+func (r *Repository) Withdraw(userID uint64, amount float64) (*AccountDTO, error) {
+	amount = roundWalletMoney(amount)
+	if userID == 0 || amount <= 0 {
+		return nil, ErrInvalidAmount
+	}
+	err := r.db.Transaction(func(tx *gorm.DB) error {
+		return AppendEntries(tx, Entry{
+			UserID:      userID,
+			Direction:   "out",
+			Amount:      amount,
+			BalanceType: "available",
+			BizType:     "withdraw_apply",
+			BizNo:       fmt.Sprintf("WD%d", time.Now().UnixNano()),
+			Remark:      "卖家申请提现",
+		})
+	})
+	if err != nil {
+		return nil, err
+	}
+	return r.Account(userID)
+}
+
 func (r *Repository) AdminLedger(query AdminLedgerQuery) (*PaginatedResult, error) {
 	db := r.db.Table("wallet_ledger AS wl").
 		Select(`wl.id, wl.ledger_no, wl.user_id, COALESCE(u.phone, '') AS user_phone,