BYGCloud OpenAI-only subscription rewriter

Subscribe with one of these URL shapes:
https://vpn.hkz.life/sub/<ACCESS_TOKEN>/cn
https://vpn.hkz.life/sub/<ACCESS_TOKEN>/overseas
https://vpn.hkz.life/provider/<ACCESS_TOKEN>/cn
https://vpn.hkz.life/provider/<ACCESS_TOKEN>/overseas
https://vpn.hkz.life/cn?token=<ACCESS_TOKEN>
https://vpn.hkz.life/overseas?token=<ACCESS_TOKEN>
https://vpn.hkz.life/cn?token=<ACCESS_TOKEN>&format=provider
https://vpn.hkz.life/overseas?token=<ACCESS_TOKEN>&format=provider