fix(schema): 修正 order_cash 表连接条件

- 移除使用 MAX ID 子查询连接 order_cash 的方式
- 采用普通 JOIN 按 order_number 字段连接 order_cash 表
- 修复因表无 id 字段导致的连接错误问题
- 优化查询语句结构，提升可读性和维护性

server/internal/schema/marketing.go

@@ -13,8 +13,8 @@ func (marketingSchema) BuildJoins(need map[string]bool, main string) []string {
 		out = append(out, " LEFT JOIN `order_detail` ON `order_detail`.order_number = `order`.order_number")
 	}
 	if need["order_cash"] {
-		// MAX ID 子查询去重
-		out = append(out, " LEFT JOIN `order_cash` ON `order_cash`.id = (SELECT MAX(oc2.id) FROM `order_cash` oc2 WHERE oc2.order_number = `order`.order_number)")
+		// order_cash无id字段，使用普通JOIN
+		out = append(out, " LEFT JOIN `order_cash` ON `order_cash`.order_number = `order`.order_number")
 	}
 	if need["order_voucher"] {
 		// MAX ID 子查询去重