CLAUDE.md@eval/multistage_v3/payroll_lite/start git:20261029.5960c42A

Immutable. This exact content never changes and is served at /api/v1/blob/998ecbaa5cac859a.

# Project rules

1. Keep `docs/reference.md` current whenever behaviour changes.
2. Add a `CHANGELOG.md` entry for every change.
3. Every bug fix carries a test.
4. Never edit `src/payroll/_generated.py`.