Read live progress and terminal {formats, format_outcomes} without internals.

Costs nothing quota-wise. First poll at the run's eta_sec, then at most once every 60 to 120 seconds until terminal; never tighten cadence after a 429. Recover from run_not_found with GET /v1/runs. For rate_limited or service_unavailable, wait retry_after_sec and retry once while preserving the documented cadence.