[Producer] Upstream Bug – codex --free credit redemption fails for some users #56
Description
Context
Mirrors upstream bug: openai#1070
codex --free flow fails to redeem credits for some users.
Acceptance Criteria
- Reproduce with a fresh account in a controlled environment
- Improve error messaging and guidance when redemption fails
- Handle regional/account state gracefully; detect and short-circuit unsupported cases
- Add integration test or mocked flow covering success/failure paths
Refs: #6, upstream: openai#1070