refactor(grpc): restructure task handling and migrate to slog

Refactor the gRPC client and task handling logic to improve modularity,
error handling, and observability.

- Split `grpc/handler.go` into specialized handler files (login,
  classroom, exams, grades, schedule) to reduce complexity.
- Replace standard `log` with `log/slog` throughout the project for
  structured logging.
- Refactor `grpc/client.go` to use a thread-safe connection management
  pattern with `sync.RWMutex`.
- Remove the legacy `service` package and HTTP server implementation,
  transitioning the application to a pure gRPC runner mode.
- Clean up `config` and `pkg/errors` to remove unused utilities and
  simplify the API.
- Improve error reporting in parsers and HTTP clients by checking
  response status codes.

client/http.go

@@ -3,41 +3,16 @@ package client
 import (
 	"log/slog"
 	"net/http"
-	"net/http/cookiejar"
-	"net/url"
 	"strings"
-	"sync"
 
 	"schedule_converter/config"
 )
 
-var (
-	Client           *http.Client
-	RecognizerClient *http.Client
-	once             sync.Once
-)
-
-func InitClient() {
-	once.Do(func() {
-		jar, err := cookiejar.New(nil)
-		if err != nil {
-			slog.Error("创建 cookie jar 失败", "error", err)
-			panic(err)
-		}
-		Client = &http.Client{Jar: jar}
-
-		cfg := config.Get()
-		RecognizerClient = &http.Client{
-			Timeout: cfg.Recognizer.Timeout,
-		}
-
-		slog.Info("HTTP 客户端初始化完成")
-	})
-}
+const defaultUserAgent = "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.36"
 
 func GetHeaders() http.Header {
 	return http.Header{
-		"User-Agent":      []string{"Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.36"},
+		"User-Agent":      []string{defaultUserAgent},
 		"Accept":          []string{"text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8"},
 		"Accept-Language": []string{"zh-CN,zh;q=0.9,en;q=0.8"},
 	}
@@ -49,15 +24,10 @@ func GetHeadersWithContentType(contentType string) http.Header {
 	return headers
 }
 
-func GetInitialCookies() error {
-	return GetInitialCookiesWithClient(Client)
-}
-
 func GetInitialCookiesWithClient(httpClient *http.Client) error {
 	slog.Info("访问登录页面获取初始Cookie")
 
-	cfg := config.Get()
-	req, err := http.NewRequest("GET", cfg.BaseURL+"/loginNOCAS", nil)
+	req, err := http.NewRequest("GET", config.Get().BaseURL+"/loginNOCAS", nil)
 	if err != nil {
 		return err
 	}
@@ -70,31 +40,13 @@ func GetInitialCookiesWithClient(httpClient *http.Client) error {
 	defer resp.Body.Close()
 
 	slog.Info("登录页面访问完成", "status_code", resp.StatusCode)
-	logCookies(httpClient)
-
 	return nil
 }
 
-func logCookies(httpClient *http.Client) {
-	cfg := config.Get()
-	cookies := httpClient.Jar.Cookies(parseURL(cfg.BaseURL))
-
-	var cookieStrs []string
-	for _, cookie := range cookies {
-		cookieStrs = append(cookieStrs, cookie.Name+"="+cookie.Value)
-	}
-	slog.Debug("当前Cookies", "cookies", strings.Join(cookieStrs, "; "))
-}
-
-func parseURL(rawURL string) *url.URL {
-	u, _ := url.Parse(rawURL)
-	return u
-}
-
 func CheckLoginSuccess(body string) bool {
 	return strings.Contains(body, "本科教学管理服务系统")
 }
 
 func IsCaptchaError(body string) bool {
 	return strings.Contains(body, "验证码")
-}
+}