CLAUDE.md@eval/multistage_v3/library_loans/start git:20261029.593764dA

Immutable. This exact content never changes and is served at /api/v1/blob/72bb9b33e58040be.

# 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/lending/_generated.py`.