_resolve_task_provider_model() flattened any explicit base_url to
provider=custom. Correct for bare/custom endpoints, but wrong for
provider-backed routes (anthropic, qwen-oauth, minimax-oauth,
openai-codex, etc.) whose provider branch adds auth refresh, transport,
or request shaping. MoA reference slots resolved through those providers
lost their identity before the aux call, so e.g. a Codex reference hit
chatgpt.com/backend-api/codex without its Cloudflare headers and got
HTML back (surfacing as a spurious rate-limit).
Keep first-class providers intact when paired with a resolved base_url
via _preserve_provider_with_base_url(); bare/custom/auto/unknown and the
direct openai alias still route through custom.
Co-authored-by: Hermes Agent <127238744+teknium1@users.noreply.github.com>
Gille
a8841e2a68