25c590ffe6
Move PDF generation from synchronous publish flow to a background polling job. Published versions with file_id IS NULL are picked up by the job, which generates the PDF, uploads to S3, and links the file. Export PDF now serves stored files for published versions (with optional signature page and watermark) and generates on the fly for drafts. Signed-off-by: Sacha Al Himdani <sacha@getprobo.com>