Stage-1 vertical slice: Pydantic Case model, SQLAlchemy Core persistence, URLhaus Scoutline fetcher, FastAPI/Jinja cockpit (cases list + detail), flat Typer CLI, Result[T, E] type module, structlog config. Architecture in docs/dossier.md; 12-fold style guide in docs/style.md. Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>