fix(exporter): 移除 order_voucher.out_biz_no 字段相关代码

- 从 sqlbuilder 中移除对 order_voucher.out_biz_no 字段的空字符串占位处理
- 从字段白名单中删除 order_voucher.out_biz_no
- 从字段标签映射中移除 order_voucher.out_biz_no 的描述信息

server/internal/exporter/sqlbuilder.go

@@ -131,11 +131,6 @@ func BuildSQLWithFields(req BuildRequest, whitelist map[string]bool) (string, []
 		if t == "order_voucher" && f == "receive_mode" {
 			// 移除枚举转换
 		}
-		if t == "order_voucher" && f == "out_biz_no" {
-			cols = append(cols, "'' AS `order_voucher.out_biz_no`")
-			usedFields = append(usedFields, tf)
-			continue
-		}
 		// Fallback for YMT tables that are not joined in schema: voucher, voucher_batch, merchant_key_send
 		if req.Datasource == "ymt" && (t == "voucher" || t == "voucher_batch" || t == "merchant_key_send") {
 			cols = append(cols, "'' AS `"+t+"."+f+"`")

server/internal/schema/fields.go

@@ -101,7 +101,6 @@ func AllWhitelist() map[string]bool {
 		"order_voucher.overdue_time":        true,
 		"order_voucher.refund_amount":       true,
 		"order_voucher.official_price":      true,
-		"order_voucher.out_biz_no":          true,
 		"order_voucher.account_no":          true,
 		"plan.id":                           true,
 		"plan.title":                        true,
@@ -324,7 +323,6 @@ func AllLabels() map[string]string {
 		"order_voucher.overdue_time":               "过期时间",
 		"order_voucher.refund_amount":              "退款金额",
 		"order_voucher.official_price":             "立减金订单.官方价",
-		"order_voucher.out_biz_no":                 "外部业务号",
 		"order_voucher.account_no":                 "账户号",
 		"order_voucher.trade_no":                   "立减金交易号",
 		"order_voucher.receive_error":              "领取错误",