Download the stored PDF (owner only)

Stream the file's stored bytes to its owner, verbatim: no view gates, no view units consumed, no readership entry, no watermark or page-range trim. Scope files:read; UUID or short id. Files you do not own, and unclaimed files, answer 404 (never 403); a link burned by its view limit answers 410. Served as Content-Type: application/pdf with Content-Disposition: inline; filename=...; Range requests are not supported. The response is binary - hand the URL to the user or save it; do not return the body to a model.