On the Publish tab, Project archive collects the Bibles, every script version, scenes, shots, the timeline, all graph edges, provenance certificates, and the full provenance of every generation — model, seed, parameters and references.
Asset binaries are referenced by URL, not embedded. A JSON document with hundreds of megabytes of base64 video inside it is not a usable archive.
It is not a restorable backup. Re-importing an archive is not implemented. This is a portable record and a hand-off document — for an audit, a rights review, or handing a project to another team — and it says so rather than letting you discover the gap after deleting the original.