refactor(check_new_email): 优化邮件通知标题显示

- 修改邮件通知标题生成逻辑，使用收件人邮箱前缀替代发件人邮箱前缀

check_new_email.py

@@ -86,11 +86,10 @@ def check_new_email(email_config: dict):
     current_email = None
     try:
         notice = AiYuFeiFei(email_config['iyuu_token'])
+        index = email_account.index("@")
+        title = f"【{email_account[:index]}】新邮件通知"
         for email in new_emails:
             current_email = email
-            sender = email['sender']
-            index = sender.index("@")
-            title = f"来自【{sender[:index]}】新的邮件"
             context = f'发件人：{email["sender"]} \n主题：{email["subject"]} \n发送时间：{email["date"]}'
             notice.send_notification(title, context)