feat(nightly): scheduled 03:10 advance pipeline (plan/orchestrate/report)
- scripts/nightly/plan.py: dependency-ordered plan from cleanup report +
CURRENT + registry (integrate candidates -> active tasks -> cleanup-ready)
- scripts/nightly/advance.py: orchestrator with reentry lock, daemon-health
preflight, headless cursor-agent advancement under agentctl leases,
queue-drain wait, env:dev rebuild + /health /ready on tip change,
no-content-loss cleanup verification, daily report draft + archival
- scripts/nightly-advance.sh: cron entrypoint
- tests: 9 unit cases for plan builder