Stage an agent's build of a workspace PDF export

Product wants an "Export workspace to PDF" button in your React app. The largest workspaces run to about 2,000 pages, so an export can take minutes, and the user gets an email with a download link when it is done. The backend is TypeScript on Node. A coding agent will build it, and you do not want one giant diff.

Write the build spec you would hand the agent: the stages in order, what each stage must deliver, and where it stops for your review.

What you know:

• the backend has a BullMQ job queue on Redis and a private S3 bucket for generated files
• an internal render service turns a page URL into a PDF, up to 200 pages per call
• a user may export only a workspace they can view, and access can be removed at any time