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## Summary
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## Test plan
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- [ ]
## Checklist
- [ ] `just pr` passes locally (fmt + clippy + tests + changed-line mutants)
- [ ] New behaviour is covered by tests where it makes sense
- [ ] Commit messages follow [conventional commits](https://www.conventionalcommits.org/) (`feat:`, `fix:`, `docs:`, …)
- [ ] User-visible changes (CLI, config, output) are reflected in the README or relevant docs