- Import: persist `has_header` flag to DB (migration v3) so headerless
CSVs like Desjardins don't lose their first data row on re-import.
- Categories: promote children to root on parent deletion instead of
cascading deactivation, preventing invisible orphans.
- Categories: add re-initialize button to reset all categories and
keywords to seed defaults.
- Bump version to 0.2.1 across tauri.conf.json, package.json, Cargo.toml.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>