<!-- overlay:python — Python idioms + validation commands to check (read-only). -->
## STACK (Python)

Beadloom validation to run (read-only): `beadloom sync-check`, `beadloom lint --strict`, `beadloom doctor`, `beadloom diff --since <base>`.

### Python idioms to check
- `dataclass(frozen=True)` for immutable models; context managers for resources (`with`).
- `pathlib.Path` not `os.path`; `str | None` not `Optional[str]`.
- Parameterized SQL (`?`, never f-strings); `yaml.safe_load` not `yaml.load`; no bare `except:`; custom exceptions inherit the project base error.
- `mypy --strict` clean; `ruff check src/ tests/` clean; no unjustified `Any` / `# type: ignore`.
