add(接口)：添加授权、用户、好友关系服务接口

backend/IM_API/Interface/Services/IAuthService.cs

@@ -0,0 +1,39 @@
+using IM_API.Dtos;
+using IM_API.Models;
+
+namespace IM_API.Interface.Services
+{
+    public interface IAuthService
+    {
+        /// <summary>
+        /// 登录
+        /// </summary>
+        /// <param name="dto"></param>
+        /// <returns></returns>
+        Task<LoginDto> LoginAsync(LoginRequestDto dto);
+        /// <summary>
+        /// 注册
+        /// </summary>
+        /// <param name="dto"></param>
+        /// <returns></returns>
+        Task<UserInfoDto> RegisterAsync(RegisterRequestDto dto);
+        /// <summary>
+        /// 生成登录凭证
+        /// </summary>
+        /// <param name="user"></param>
+        /// <returns></returns>
+        string GenerateToken(User user);
+        /// <summary>
+        /// 验证登录凭证
+        /// </summary>
+        /// <param name="token"></param>
+        /// <returns></returns>
+        int? ValidateToken(string token);
+        /// <summary>
+        /// 刷新令牌
+        /// </summary>
+        /// <param name="refreshToken"></param>
+        /// <returns></returns>
+        LoginDto RefreshToken(string refreshToken);
+    }
+}