feat(grpc): enhance grades and exams data structures

Update the gRPC service definitions and handlers to provide more detailed
information for grades and exams.

- Add `GpaSummary` message to include average GPA, rank, and other
  academic statistics.
- Expand `Grade` message with additional fields like `term`, `nature`,
  `category`, and `is_exam`.
- Refactor `Exam` message to use `week` and `weekday` instead of `room`
  and `seat`.
- Update `TaskHandler.getGrades` to populate the new `GpaSummary` and
  enriched grade details.
- Update protobuf generated files to reflect schema changes.

grpc/handler.go

@@ -8,8 +8,6 @@ import (
 	"net/http"
 	"net/http/cookiejar"
 	"net/url"
-	"strconv"
-	"strings"
 	"sync"
 	"time"
 
@@ -247,21 +245,32 @@ func (h *TaskHandler) getGrades(ctx context.Context, payload []byte) ([]byte, er
 		return nil, err
 	}
 
-	_, grades, err := parser.FetchGPA(httpClient)
+	var gpaSummary *pb.GpaSummary
+	summary, grades, err := parser.FetchGPA(httpClient)
 	if err != nil {
 		log.Warn("获取GPA页面失败，尝试成绩页面", "error", err)
 		grades, err = parser.FetchGrades(httpClient, parser.ScoreTypeFinal)
 		if err != nil {
 			return nil, apperr.New("fetch_grades", err, "获取成绩失败")
 		}
+	} else if summary != nil {
+		gpaSummary = &pb.GpaSummary{
+			AverageGpa:      summary.AverageGPA,
+			Rank:            summary.Rank,
+			ExamTotalGpa:    summary.ExamTotalGPA,
+			ExamTotalCredits: summary.ExamTotalCredits,
+			FailCredits:     summary.FailCredits,
+			Semesters:       summary.Semesters,
+		}
 	}
 
 	pbGrades := convertGrades(grades)
 
 	result := &pb.GradesResultData{
-		StudentId: req.Username,
-		Semester:  req.Semester,
-		Grades:    pbGrades,
+		StudentId:  req.Username,
+		Semester:   req.Semester,
+		Grades:     pbGrades,
+		GpaSummary: gpaSummary,
 	}
 
 	log.Info("成绩获取成功", "grade_count", len(pbGrades))
@@ -338,20 +347,16 @@ func convertToInt32(arr []int) []int32 {
 func convertGrades(grades []parser.GradeEntry) []*pb.Grade {
 	result := make([]*pb.Grade, 0, len(grades))
 	for _, g := range grades {
-		var credit float32
-		if v, err := parseFloat(g.Credit); err == nil {
-			credit = v
-		}
-		var gradePoint float32
-		if v, err := parseFloat(g.GradePoint); err == nil {
-			gradePoint = v
-		}
 		result = append(result, &pb.Grade{
+			Term:       g.Term,
 			CourseCode: g.Code,
 			CourseName: g.Name,
-			Credit:     credit,
-			Grade:      g.Score,
-			GradePoint: gradePoint,
+			Nature:     g.Nature,
+			Category:   g.Category,
+			Credit:     g.Credit,
+			Score:      g.Score,
+			GradePoint: g.GradePoint,
+			IsExam:     g.IsExam,
 		})
 	}
 	return result
@@ -372,21 +377,9 @@ func convertExams(exams []parser.ExamEntry) []*pb.Exam {
 			ExamType:   examTypeStr,
 			Date:       e.Date,
 			Time:       e.Time,
-			Room:       e.Week,
-			Seat:       e.Weekday,
+			Week:       e.Week,
+			Weekday:    e.Weekday,
 		})
 	}
 	return result
 }
-
-func parseFloat(s string) (float32, error) {
-	s = strings.TrimSpace(s)
-	if s == "" || s == "-" {
-		return 0, fmt.Errorf("empty")
-	}
-	v, err := strconv.ParseFloat(s, 32)
-	if err != nil {
-		return 0, err
-	}
-	return float32(v), nil
-}