Implement endpoints in more flexible way.

Fix: re-implement `UserEndpoint` as static style which works best with minimal API, simplify the DI framework.

Fix: remove no needed service register in main program.

OptixServe.Api/Endpoints/UserEndpoint.cs

@@ -9,34 +9,26 @@ namespace OptixServe.Api.Endpoints;
 [JsonSerializable(typeof(IEnumerable<UserDto>))]
 public partial class UserJsonContext : JsonSerializerContext { }
 
-public class UserEndpoint
+public static class UserEndpoint
 {
-    private readonly IUserService _userService;
-
-    // 通过构造函数注入依赖
-    public UserEndpoint(IUserService userService)
-    {
-        _userService = userService;
-    }
-
     public static void Register(WebApplication app)
     {
         var group = app.MapGroup("/users");
 
-        group.MapGet("/", (UserEndpoint endpoint) => endpoint.GetAllUsers());
-        group.MapGet("/{id}", (string id, UserEndpoint endpoint) => endpoint.GetUserById(id));
+        group.MapGet("/", GetAllUsers);
+        group.MapGet("/{id}", GetUserById);
     }
 
-    public IResult GetAllUsers()
+    public static IResult GetAllUsers(IUserService userService)
     {
-        var users = _userService.GetUsers()
+        var users = userService.GetUsers()
             .Select(u => new UserDto { Id = u.Id, UserName = u.UserName });
         return Results.Ok(users);
     }
 
-    public IResult GetUserById(string id)
+    public static IResult GetUserById(string id, IUserService userService)
     {
-        var user = _userService.GetUserById(id);
+        var user = userService.GetUserById(id);
         if (user == null)
             return Results.NotFound();