- Add fiveHourReset/weeklyReset to statusPayload and aggregatedStatus
with weight-averaged reset time aggregation across credential pools
- Rewrite response headers (utilization + reset times) for all users,
not just external credential users
- Rewrite WebSocket rate_limits events for all users with aggregated values
- Add proactive WebSocket status push: synthetic codex.rate_limits events
sent on connection start and on status changes via statusObserver
- Remove one-shot stream forward compatibility (statusStreamHeader,
restoreLastUpdatedIfUnchanged, oneShot detection)