feat(system): 新增租户超级管理员用户ID字段

- Tenant实体类中新增superAdminUserId字段，标记为非数据库字段
- 在TenantMapper.xml的关联查询SQL中添加超级管理员用户ID字段查询
- 用于前端或业务逻辑识别租户对应的超级管理员用户ID，便于权限管理

src/main/java/com/gxwebsoft/common/system/entity/Tenant.java

@@ -104,6 +104,10 @@ public class Tenant implements Serializable {
   @TableField(exist = false)
   private String phone;
 
+  @Schema(description = "超级管理员用户ID")
+  @TableField(exist = false)
+  private Integer superAdminUserId;
+
   @Schema(description = "管理地址")
   @TableField(exist = false)
   private String adminUrl;

src/main/java/com/gxwebsoft/common/system/mapper/xml/TenantMapper.xml

@@ -5,7 +5,7 @@
     <!-- 关联查询sql -->
     <sql id="selectSql">
         SELECT a.*,b.company_name,b.company_logo as logo,b.admin_url,b.domain,b.free_domain,
-               u.phone,u.username
+               u.phone,u.username,u.user_id as superAdminUserId
         FROM sys_tenant a
         LEFT JOIN sys_company b ON a.tenant_id = b.tenant_id
         LEFT JOIN gxwebsoft_core.sys_user u ON u.tenant_id = a.tenant_id AND u.is_super_admin = 1 AND u.deleted = 0