//! The project's state tree on disk: where it is anchored (`paths`), how a source
//! asset is found inside it (`source`), and how the compiled blob is read out of
//! it (`blob`).
//!
//! This is the engine's only home for filesystem knowledge below the engine and
//! cook crates. concinnity-blob owns the pure bytes <-> metadata transforms and
//! performs no I/O; concinnity-core owns the runtime blob types and the
//! `PayloadStore` seam and knows neither paths nor files. The reads that join the
//! two live here.