refactor: Introduce pre-consume quota and unify relay handlers

This commit introduces a major architectural refactoring to improve quota management, centralize logging, and streamline the relay handling logic.

Key changes:
- **Pre-consume Quota:** Implements a new mechanism to check and reserve user quota *before* making the request to the upstream provider. This ensures more accurate quota deduction and prevents users from exceeding their limits due to concurrent requests.

- **Unified Relay Handlers:** Refactors the relay logic to use generic handlers (e.g., `ChatHandler`, `ImageHandler`) instead of provider-specific implementations. This significantly reduces code duplication and simplifies adding new channels.

- **Centralized Logger:** A new dedicated `logger` package is introduced, and all system logging calls are migrated to use it, moving this responsibility out of the `common` package.

- **Code Reorganization:** DTOs are generalized (e.g., `dalle.go` -> `openai_image.go`) and utility code is moved to more appropriate packages (e.g., `common/http.go` -> `service/http.go`) for better code structure.

controller/github.go

@@ -7,6 +7,7 @@ import (
 	"fmt"
 	"net/http"
 	"one-api/common"
+	"one-api/logger"
 	"one-api/model"
 	"strconv"
 	"time"
@@ -47,7 +48,7 @@ func getGitHubUserInfoByCode(code string) (*GitHubUser, error) {
 	}
 	res, err := client.Do(req)
 	if err != nil {
-		common.SysLog(err.Error())
+		logger.SysLog(err.Error())
 		return nil, errors.New("无法连接至 GitHub 服务器，请稍后重试！")
 	}
 	defer res.Body.Close()
@@ -63,7 +64,7 @@ func getGitHubUserInfoByCode(code string) (*GitHubUser, error) {
 	req.Header.Set("Authorization", fmt.Sprintf("Bearer %s", oAuthResponse.AccessToken))
 	res2, err := client.Do(req)
 	if err != nil {
-		common.SysLog(err.Error())
+		logger.SysLog(err.Error())
 		return nil, errors.New("无法连接至 GitHub 服务器，请稍后重试！")
 	}
 	defer res2.Body.Close()