concinnity-world: the build-side world front half.
Owns the authored world model (world.jsonl parsing and I/O, structural
validation), the authoring type vocabulary (RegisteredType, instantiated
from the shared registry list in concinnity-core), the asset
cross-reference metadata, semantic validation
(check), the typed authoring vocabulary (spec), and the world templates
built from it (template). Everything here operates on the authored input;
the shipped runtime plays compiled blobs and never links this crate.
Deliberately excluded: build-time expansion (SceneImport, prefabs, injection
passes), importers/encoders, payload compilation, and blob writing -- all of
that is concinnity-cook, which sits on top of this crate and composes its
compile-backed per-asset checks through check::check_world_with.
The authored medium is JSON (an asset's args is its public JSON schema), so
serde_json is intrinsic to this crate's job; typed struct-first authoring is
served by spec's AssetSpec builders, converted to world entries by
spec::json.