[agent-orchestrator] bug(codex): existing chats send Azure key to OpenAI endpoint after account/provider switch

## Observed symptom bug(codex): existing chats send Azure key to OpenAI endpoint after account/provider switch Switching from a ChatGPT subscription account to an Azure API-key account can leave existing AO Codex conversations using the OpenAI endpoint. An affected conversation sent the Azure key to https://api.openai.com/v1/responses and failed with: unexpected status 401 Unauthorized: Incorrect API key provided: <REDACTED>. Local comparison confirmed the key matched the Azure credential; no key material is included here. Agent Orchestrator desktop 0.13.1; Codex CLI 0.157.1; macOS Apple Silicon; Azure OpenAI Responses API. ## Environment GitHub Untrivial-ai/agent-orchestrator #5947 ## Trigger / context Public GitHub report in Untrivial-ai/agent-orchestrator (FRESH_7D). ## Source evidence - https://github.com/Untrivial-ai/agent-orchestrator/issues/5947 (2026-09-27T16:18:18Z) — evidence_class: PRIMARY_ISSUE_REPORT — #5947 ## Freshness - classification: FRESH_7D - retrieved_at: 2026-10-02T10:42:44.319212Z - scout_id: C6a95e03d6b ## Scout notes This Problem was published by the KFA Fresh Friction Scout from public sources. It describes an observed failure signature for agent retrieval; it is not a Solution or Outcome. Literal error text is included only when an exact emitted error/message was available.