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.Server/Controllers/StudentSubmissionController.cs

@@ -0,0 +1,127 @@
+using Entities.Contracts;
+using Entities.DTO;
+using Microsoft.AspNetCore.Authorization;
+using Microsoft.AspNetCore.Identity;
+using Microsoft.AspNetCore.Mvc;
+using TechHelper.Server.Services;
+using System.Security.Claims;
+
+namespace TechHelper.Server.Controllers
+{
+    [Route("api/student-submission")]
+    [ApiController]
+    [Authorize]
+    public class StudentSubmissionController : ControllerBase
+    {
+        private readonly IStudentSubmissionService _studentSubmissionService;
+        private readonly UserManager<User> _userManager;
+
+        public StudentSubmissionController(
+            IStudentSubmissionService studentSubmissionService,
+            UserManager<User> userManager)
+        {
+            _studentSubmissionService = studentSubmissionService;
+            _userManager = userManager;
+        }
+
+        /// <summary>
+        /// 获取当前学生的所有提交摘要
+        /// </summary>
+        /// <returns>学生提交摘要列表</returns>
+        [HttpGet("my-submissions")]
+        public async Task<IActionResult> GetMySubmissions()
+        {
+            var user = await _userManager.FindByEmailAsync(User.Identity.Name);
+            if (user == null)
+                return NotFound("未找到用户信息");
+
+            var result = await _studentSubmissionService.GetStudentSubmissionsAsync(user.Id);
+
+            if (result.Status)
+            {
+                return Ok(result.Result);
+            }
+            else
+            {
+                return BadRequest(result.Message);
+            }
+        }
+
+        /// <summary>
+        /// 获取当前学生的提交摘要（分页）
+        /// </summary>
+        /// <param name="pageNumber">页码，默认为1</param>
+        /// <param name="pageSize">每页数量，默认为10</param>
+        /// <returns>分页的学生提交摘要列表</returns>
+        [HttpGet("my-submissions-paged")]
+        public async Task<IActionResult> GetMySubmissionsPaged(int pageNumber = 1, int pageSize = 10)
+        {
+            if (pageNumber < 1) pageNumber = 1;
+            if (pageSize < 1) pageSize = 10;
+            if (pageSize > 100) pageSize = 100; // 限制最大页面大小
+
+            var user = await _userManager.FindByEmailAsync(User.Identity.Name);
+            if (user == null)
+                return NotFound("未找到用户信息");
+
+            var result = await _studentSubmissionService.GetStudentSubmissionsPagedAsync(user.Id, pageNumber, pageSize);
+
+            if (result.Status)
+            {
+                return Ok(result.Result);
+            }
+            else
+            {
+                return BadRequest(result.Message);
+            }
+        }
+
+        /// <summary>
+        /// 获取指定学生的提交摘要（仅教师可使用）
+        /// </summary>
+        /// <param name="studentId">学生ID</param>
+        /// <returns>学生提交摘要列表</returns>
+        [HttpGet("student/{studentId:guid}")]
+        [Authorize(Roles = "Teacher")]
+        public async Task<IActionResult> GetStudentSubmissions(Guid studentId)
+        {
+            var result = await _studentSubmissionService.GetStudentSubmissionsAsync(studentId);
+
+            if (result.Status)
+            {
+                return Ok(result.Result);
+            }
+            else
+            {
+                return BadRequest(result.Message);
+            }
+        }
+
+        /// <summary>
+        /// 获取指定学生的提交摘要（分页，仅教师可使用）
+        /// </summary>
+        /// <param name="studentId">学生ID</param>
+        /// <param name="pageNumber">页码，默认为1</param>
+        /// <param name="pageSize">每页数量，默认为10</param>
+        /// <returns>分页的学生提交摘要列表</returns>
+        [HttpGet("student/{studentId:guid}/paged")]
+        [Authorize(Roles = "Teacher")]
+        public async Task<IActionResult> GetStudentSubmissionsPaged(Guid studentId, int pageNumber = 1, int pageSize = 10)
+        {
+            if (pageNumber < 1) pageNumber = 1;
+            if (pageSize < 1) pageSize = 10;
+            if (pageSize > 100) pageSize = 100; // 限制最大页面大小
+
+            var result = await _studentSubmissionService.GetStudentSubmissionsPagedAsync(studentId, pageNumber, pageSize);
+
+            if (result.Status)
+            {
+                return Ok(result.Result);
+            }
+            else
+            {
+                return BadRequest(result.Message);
+            }
+        }
+    }
+}