删除了ai识别验证码部分，新增个人成绩补考标识和cet成绩查询

service/grades.go

@@ -78,6 +78,7 @@ func convertGrades(grades []models.GradeEntry) []*pb.Grade {
 			Score:      g.Score,
 			GradePoint: g.GradePoint,
 			IsExam:     g.IsExam,
+			IsRetake:   g.IsRetake,
 		})
 	}
 	return result

service/service.go

@@ -58,7 +58,7 @@ func (s *Service) setTWFIDCookie(httpClient *http.Client, baseURL, twfid string)
 	})
 }
 
-// login 执行登录流程，包含验证码识别与重试。
+// login 执行登录流程，验证码固定使用占位值 "...."。
 func (s *Service) login(ctx context.Context, httpClient *http.Client, username, password string) error {
 	log := slog.With("username", username)
 
@@ -75,13 +75,7 @@ func (s *Service) login(ctx context.Context, httpClient *http.Client, username,
 
 		log.Info("尝试登录", "attempt", attempt, "max_retries", maxLoginRetries)
 
-		captchaCode, err := captcha.GetAndRecognize(httpClient)
-		if err != nil {
-			log.Warn("验证码获取失败", "error", err, "attempt", attempt)
-			time.Sleep(loginRetryInterval)
-			continue
-		}
-
+		captchaCode := captcha.GetCaptchaCode()
 		success, err := auth.LoginWithClient(ctx, httpClient, captchaCode, username, password)
 		if err != nil {
 			log.Warn("登录请求失败", "error", err, "attempt", attempt)