## 1. Implementation
- [x] Add regression coverage for rapid stop/start while the first run is still finalizing.
- [x] Move finalization and summary reads/writes to per-run meeting note and artifact state.
- [x] Make rapidly-created artifact filenames distinct.

## 2. Verification
- [x] Run focused recording coordinator tests.
- [x] Run `openspec validate allow-overlapping-meeting-finalization --strict`.