fix: 添加TaskApprovalService依赖并使用@Lazy解决循环依赖

backend/src/main/java/com/designhub/service/TaskService.java

@@ -64,6 +64,8 @@ public class TaskService {
     private final com.designhub.mapper.DepartmentMapper departmentMapper;
     private final com.designhub.util.WorkHoursCalculator workHoursCalculator;
     private final com.designhub.mapper.DelayPenaltyRecordMapper delayPenaltyRecordMapper;
+    @org.springframework.context.annotation.Lazy
+    private final TaskApprovalService taskApprovalService;
 
     /**
      * 创建任务