Per Codex: the Next poll column computed only the streak-backoff time, so a
rate-limited source could show an earlier Next poll than the real gate (which
also requires retry_after_at <= now). Take the later of the two in the Python
post-process so the admin table agrees with due_source_rows.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Per Codex's spec — a publisher saying "slow down" shouldn't make a feed look
broken, but repeated 429s stay visible via last_success_at / stale-source.
* Schema: sources.retry_after_at (nullable) + migration.
* feeds.parse_retry_after: delta-seconds OR HTTP-date → UTC stamp; ignores
invalid/negative/past; caps at now + MAX_BACKOFF_MINUTES.
* fetch_feed raises RateLimited (carrying the parsed time) on a 429.
* poll_source: on 429 set retry_after_at + last_error, status='rate_limited',
and do NOT increment consecutive_failures; on success clear retry_after_at;
non-429 failures unchanged.
* due_source_rows requires BOTH the streak backoff elapsed AND retry_after_at
passed (i.e. the later of the two).
* Admin: source_health returns retry_after_at; status reads
"rate-limited · rests until …" rather than "failed/resting".
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>