Project environment — the project-as-crate authoring loop
Realizes the engine/project separation (domain invariant 9 / C16, docs/design/INDEX.md) as working machinery: a research project is an external Rust cdylib crate of node/strategy blueprints plus a static Aura.toml, scaffolded by aura new, discovered cargo-style by walking up to Aura.toml, loaded per invocation through the injected vocabulary-resolver seam blueprint loading already exposes (blueprint_from_json, crates/aura-engine/src/blueprint_serde.rs:165), and driven end-to-end by the existing blueprint verbs.
In scope: the cdylib load contract (load-and-hold lifetime, same-toolchain check), the project-resolver charter (project vocabulary plus std vocabulary, collision policy), the Aura.toml v1 schema, content-id canonicalization ahead of the first external consumer (#171), the aura new scaffolder, an authoring-loop end-to-end path, and a milestone fieldtest as a genuine external project crate.
Out of scope, deferred: experiments-in-crate (#147), freeze/deploy and the live broker edge (#149), and the hard-wired-harness retirement (#159).
Decision provenance, the recorded sequencing revision, and the full scope detail: #180.
