Bulk

Returns the job envelope plus its per-URL items. **Downloading item content.** Each completed item's `content_url` is a **pre-signed** URL, minted fresh on every read of this endpoint and valid for **600 seconds (10 minutes)** — the same signing lifetime as the `image_url` returned by `GET /v1/bulk/{id}/screenshots`. The underlying objects are private, so an unsigned URL returns `401`: download the content inside that window, or re-poll this endpoint for a fresh signature. Items that are not `completed`, and completed items with no stored object, carry `null` or the unsigned stored URL instead.