pub fn provision(models_root: &Path) -> Result<PathBuf>Expand description
Ensure sd-cli is installed under <models_root>/bin/, downloading
and extracting the platform’s stable-diffusion.cpp build when it’s
missing. Returns the resolved binary path. Idempotent: a binary
already present short-circuits the download.
Excluded from coverage: drives a real network download + filesystem
extraction. The pure pieces it composes ([asset_name],
[download_url], [install_dir], library_path_env) and the
full path against a served fake zip are covered by tests.