laneRank() lumped a held (stopped) phase in with unstarted phases at
the same rank, so an actionable "stopped — held by …" lane could sort
below phases nobody has started. The snapshot already carries
snap.stopped, so give a held run its own rank just below running,
keeping it near the top where a person can resume it. Addresses the
Copilot review point on PR #48.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>