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### PR [#2200](https://github.com/danielmiessler/Fabric/pull/2200) by [ksylvan](https://github.com/ksylvan): fix: persist Codex OAuth tokens after refresh

- Fixed Codex OAuth token persistence so refreshed credentials are securely retained across processes.
- Persisted rotated Codex credentials atomically using cross-process locks, and reloaded stored tokens before refresh to prevent stale rotations.
- Preserved existing environment values while enforcing secret-only file permissions.
- Reactivated configured vendors and surfaced configuration failures immediately.
- Reused valid refresh tokens before launching interactive authentication.