docs: introduce docs/archive, remove finished sprint boards and generated report
- docs/archive/2026/ with index README: DR tabletop drill, workstation
audits, HA/Ecowitt draft, pre-Borg backup audit, finished windows
reinstall project docs
- delete weekend sprint boards (content preserved in MASTER_TODO done log
and git history)
- untrack generated ops/policy-checks/last-report.md and gitignore it
- fix references (CLAUDE.md, docs/README.md, ops/windows-reinstall/README.md)
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Micha
c80b51f585