refactor(service): 修改IEntityService泛型为VO类型并优化缓存策略

重构所有注解@CacheConfig的Service类，将IEntityService泛型从实体类改为VO类
实现实体与VO之间的转换逻辑，使用VO替代实体进行缓存以避免序列化问题
更新相关依赖组件和测试用例，确保功能完整性和系统兼容性
优化Redis缓存配置，清理旧缓存数据并验证新缓存策略有效性

server/src/main/java/com/ecep/contract/controller/IndexController.java

@@ -1,9 +1,17 @@
 package com.ecep.contract.controller;
 
 import org.springframework.http.ResponseEntity;
+import org.springframework.security.core.Authentication;
+import org.springframework.security.core.context.SecurityContext;
+import org.springframework.security.core.context.SecurityContextHolder;
+import org.springframework.security.core.userdetails.UserDetails;
 import org.springframework.web.bind.annotation.GetMapping;
 import org.springframework.web.bind.annotation.RestController;
 
+import com.ecep.contract.SpringApp;
+import com.ecep.contract.ds.other.service.EmployeeService;
+import com.ecep.contract.model.Employee;
+
 /**
  * 基础控制器，处理根路径请求
  */
@@ -15,7 +23,22 @@ public class IndexController {
      */
     @GetMapping("/")
     public ResponseEntity<?> index() {
-        return ResponseEntity.ok("合同管理系统 REST API 服务已启动");
+        SecurityContext securityContext = SecurityContextHolder.getContext();
+        Authentication authentication = securityContext.getAuthentication();
+
+        Object principal = authentication.getPrincipal();
+        if (principal instanceof UserDetails userDetails) {
+            System.out.println(userDetails.getUsername());
+            EmployeeService employeeService = SpringApp.getBean(EmployeeService.class);
+            try {
+                Employee employee = employeeService.findByAccount(userDetails.getUsername());
+                return ResponseEntity.ok(employee);
+            } catch (Exception e) {
+                e.printStackTrace();
+            }
+        }
+
+        return ResponseEntity.ok(authentication);
     }
 
 }