The Codex PR introduced a second isCodexSubscriber() definition that
silently overwrote the first. The replacement only checked for token
existence, ignoring the active provider — so once a user authenticated
with Codex, all requests were permanently routed to the Codex endpoint
regardless of model selection.
Merged both functions into one that requires the provider to be
explicitly set to 'openai' before returning true.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
