style: 重新调整一下后端的结构，并通过csharpier格式化

server/src/Controllers/TutorialController.cs

@@ -0,0 +1,55 @@
+using System.IO;
+using System.Collections.Generic;
+using Microsoft.AspNetCore.Mvc;
+
+namespace server.Controllers;
+
+/// <summary>
+/// 教程 API
+/// </summary>
+[ApiController]
+[Route("api/[controller]")]
+public class TutorialController : ControllerBase
+{
+    private static NLog.Logger logger = NLog.LogManager.GetCurrentClassLogger();
+    private readonly IWebHostEnvironment _environment;
+
+    public TutorialController(IWebHostEnvironment environment)
+    {
+        _environment = environment;
+    }
+
+    /// <summary>
+    /// 获取所有可用的教程目录
+    /// </summary>
+    /// <returns>教程目录列表</returns>
+    [HttpGet]
+    [ProducesResponseType(StatusCodes.Status200OK)]
+    [ProducesResponseType(StatusCodes.Status500InternalServerError)]
+    public IActionResult GetTutorials()
+    {
+        try
+        {
+            // 获取文档目录
+            string docPath = Path.Combine(_environment.WebRootPath, "doc");
+            
+            if (!Directory.Exists(docPath))
+            {
+                return Ok(new { tutorials = new List<string>() });
+            }
+
+            // 获取所有子目录
+            var directories = Directory.GetDirectories(docPath)
+                .Select(Path.GetFileName)
+                .Where(dir => !string.IsNullOrEmpty(dir))
+                .ToList();
+
+            return Ok(new { tutorials = directories });
+        }
+        catch (Exception ex)
+        {
+            logger.Error(ex, "获取教程目录失败");
+            return StatusCode(500, new { error = "无法读取教程目录" });
+        }
+    }
+}