f05e0cbe99
extractRetryableSignal returns the raw isRetryable hint from up to 5
nested AI SDK error paths. isRetryableError previously trusted any
true result blindly, which would burn every configured fallback model
in an infinite loop if a provider mis-tagged a 401, 403, or other
non-transient 4xx as retryable.
Honor the signal only when the status code is absent, in the configured
retry_on_errors list, in 5xx, or in {408, 425, 429}. Reject the signal
when the status code is a non-transient 4xx and log the rejection so
operators can debug provider mis-classifications.
Closes pre-publish blocker V8.