feat: 添加学生提交系统功能

- 添加学生提交管理服务 (StudentSubmissionService, StudentSubmissionDetailService)
- 新增学生提交相关控制器 (StudentSubmissionController, StudentSubmissionDetailController)
- 添加学生提交数据传输对象 (StudentSubmissionDetailDto, StudentSubmissionSummaryDto)
- 新增学生提交相关页面组件 (StudentExamView, ExamDetailView, StudentCard等)
- 添加学生提交信息卡片组件 (SubmissionInfoCard, TeacherSubmissionInfoCard)
- 更新数据库迁移文件以支持提交系统

TechHelper.Client/Services/ClasssServices.cs

@@ -54,6 +54,11 @@ namespace TechHelper.Client.Services
 			}
 		}
 
+		public StudentDto GetStudents(byte Class)
+		{
+			throw new NotImplementedException();
+		}
+
 		public async Task<ResponseDto> UserRegister(UserRegistrationToClassDto userRegistrationToClassDto)
 		{
 			try