Create or Check a Busy Purchase Register Export

How it behaves

Use this only when the user explicitly asks to download or export a potentially large Busy purchase or purchase-return register without placing raw rows in model context. For operation=create, provide company_code, financial_year, and grain; optionally narrow dates and exact entities or apply catalog-resolved dimension_filters compatible with the selected voucher/product_line grain. Resolve configurable labels and values with busy_get_dimension_catalog; never guess OF meanings. For operation=status, provide only job_id and poll until the signed download is ready. Do not use this for totals, rankings, trends, payables, procurement analysis, or client-side grouping. This creates private job/file state but never changes Busy accounting data.