- Add StatusEnrichmentStarted/PageFetched/Writing progress events so
sync no longer has a 45-60s silent gap during GraphQL status fetch
- Thread per-page callback into fetch_issue_statuses_with_progress
- Hide status_category from all human and robot output (keep in DB)
- Add meta.available_statuses to issues list JSON response for agent
self-discovery of valid --status filter values
- Update robot-docs with status filtering documentation
