feat: Implement ChatGPT account registration flow and establish core backend API infrastructure with logging utilities.

backend/internal/register/chatgpt.go

@@ -301,7 +301,7 @@ func APIRegister(email, password, realName, birthdate, proxy string, logPrefix s
 
 		fpInfo := reg.Client.GetFingerprintInfo()
 		if retry == 0 {
-			logger.Info(fmt.Sprintf("%s 初始化会话... [%s]", logPrefix, fpInfo), email, "register")
+			logger.Status(fmt.Sprintf("%s 初始化会话... [%s]", logPrefix, fpInfo), email, "register")
 		} else {
 			logger.Warning(fmt.Sprintf("%s 403 重试 %d/3，换指纹 [%s]", logPrefix, retry, fpInfo), email, "register")
 		}
@@ -343,10 +343,9 @@ func APIRegister(email, password, realName, birthdate, proxy string, logPrefix s
 	if err := reg.SendVerificationEmail(); err != nil {
 		return nil, fmt.Errorf("发送验证邮件失败: %v", err)
 	}
-	logger.Success(fmt.Sprintf("%s 已发送验证邮件", logPrefix), email, "register")
 
-	// 获取验证码 (带超时 90s)
-	logger.Info(fmt.Sprintf("%s 等待验证码...", logPrefix), email, "register")
+	// 获取验证码 (带超时 90s) - 合并日志，使用 Status 显示等待状态
+	logger.Status(fmt.Sprintf("%s 验证邮箱中...", logPrefix), email, "register")
 	otpCode, err := mail.GetVerificationCode(email, 90*time.Second)
 	if err != nil {
 		return nil, err