Stream the master catalog as a CSV file. The CSV emits 7 columns: master_product_id, name, brand, category, sku, price, stock_level. master_product_id, name, brand, and category are pre-filled from the master record; sku, price, stock_level are emitted blank. Vendors fill the blank columns offline and re-upload via the CSV-match flow at POST /products/master-catalog/import. Rows with a populated master_product_id skip fuzzy matching and resolve directly. The product status (draft / published) is controlled by the upload form's default_status field — it applies to every row in the upload.

Accepts the same filters as the catalog browse endpoint, so vendors can export a filtered subset.