openai-codex provider crashes with TypeError: 'NoneType' object is not iterable on every request (chatgpt.com sends output: null in response.completed event)

The openai-codex provider crashes on every request after a gateway restart with a TypeError, because the chatgpt.com Codex endpoint returns output: null in response.completed events, which OpenAI SDK 2.24.0's parser cannot handle; this uncaught error drains the credential pool. Issue is closed as fixed.