When /agent-loop:run detects a previous run with all stories passed (or the
feature branch deleted after merge), it archives the old artifacts and resets
.loop/ automatically — no more manual rm -rf .loop.
- Add archive_and_reset() for on-demand archiving from skills
- Add runs.log index tracking all archived runs
- Update /run and /stories skills to detect completed runs
- setup.sh archives instead of hard-failing when prd.json exists
- Bump version to 0.9.0