please add fallback API key feature

What version of Codex is running?

0.91

What subscription do you have?

GPT+ and API Key subscription

Which model were you using?

codex-5.2

What platform is your computer?

Fedora linux 42, windows 11

What terminal emulator and version are you using (if applicable)?

Powershel & Terminal

What issue are you seeing?

when the tokens of 5 Hours or one week are consumed, I have to log out and enter my api key in order to continue working. This is quite annoying since I am using codex a lot. And I have to constantly switch btween the two.

What steps can reproduce the bug?

Uploaded thread: 019c0506-0dfe-7aa3-b566-5a23119fb18c

1. Use Codex, consume all tokens included in your substription
2. You need to log out and log in with an api key to continue
3. Once the subscription tokens are renewed, log out again and proceed with an openai device authentication.

This gets especially annoying when you have multiple devices which codex is managing and you have to log out and log in every time newly...

What is the expected behavior?

1. Log in with openai account or api key
2. Allow connecting a fallback account (openao account or api key)

-> consume tokens from account 1.
-> When account 1 is depleted, consume tokens from api key subscription configured in 2.

Additional information

_No response_