feat: 添加员工门户项目及相关后端改造

- 新增 hzhub-portal-employee 员工门户前端项目（基于 Vue3 + Element Plus）
- 后端登录接口增加返回 nickName 字段
- 移除 KnowledgeInfoController 的 @SaCheckPermission 注解
- 删除 hzhub-portal-company 旧门户项目
- 更新项目文档和架构说明
- 添加后台运行管理脚本（start-all.sh / status-all.sh / stop-all.sh）
- 更新 docker-compose 配置

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

docs/architecture/hzhub-architecture.dot

@@ -18,7 +18,7 @@ digraph HZHubArchitecture {
         labeljust=left;
 
         admin [label="hzhub-admin\nManagement Portal\n• Model Management\n• Knowledge Base Config\n• Agent Orchestration", fillcolor="#BBDEFB", color="#1976D2"];
-        company [label="hzhub-portal-company\nCompany Portal\n• WeChat Work H5\n• Approval Workflow\n• Sales CRM\n• BI Reports", fillcolor="#BBDEFB", color="#1976D2"];
+        company [label="hzhub-portal-employee\nEmployee Portal\n• WeChat Work H5\n• Approval Workflow\n• Sales CRM\n• BI Reports", fillcolor="#BBDEFB", color="#1976D2"];
         dealer [label="hzhub-portal-dealer\nDealer Portal\n• WeChat Work H5\n• Self-service Order\n• Inventory Mgmt\n• AI Material Gen", fillcolor="#BBDEFB", color="#1976D2"];
     }