Builds
A Build is an immutable mobile artifact record tied to one App and Environment.
Lifecycle: pending_upload → ready → deleting → deleted.
A ready Build stores parsed app identity, version/build number, platform/artifact type, SHA-256, release notes, provenance and the private R2 object locator. Artifact bytes are served with short-lived capabilities rather than proxied through the API.
Derived re-signed Builds keep immutable source_build_id lineage. Updating release notes does not mutate artifact bytes or identity.