fix(database): 修复导航查询中的数据库连接条件问题

- 为父级导航连接添加删除状态和租户ID过滤条件
- 移除模型连接中不必要的 c.model = 0 条件以避免字符串转数字比较
- 为模型连接添加删除状态和租户ID过滤条件
- 添加注释说明原条件导致的性能问题

src/main/java/com/gxwebsoft/cms/mapper/xml/CmsNavigationMapper.xml

@@ -6,8 +6,9 @@
     <sql id="selectSql">
         SELECT a.*, b.title as parentName, b.position as parentPosition, c.name as modelName
         FROM cms_navigation a
-        LEFT JOIN cms_navigation b ON a.parent_id = b.navigation_id
-        LEFT JOIN cms_model c ON a.model = c.model AND c.model = 0
+        LEFT JOIN cms_navigation b ON a.parent_id = b.navigation_id AND b.deleted = 0 AND b.tenant_id = a.tenant_id
+        <!-- c.model = 0 会触发 MySQL 字符串转数字比较，导致几乎所有模型都匹配，从而把导航行成倍放大 -->
+        LEFT JOIN cms_model c ON a.model = c.model AND c.deleted = 0 AND c.tenant_id = a.tenant_id
         <where>
             <if test="param.navigationId != null">
                 AND a.navigation_id = #{param.navigationId}