Previously a PO's free-text line items only became reusable catalogue products
(/inventory/items) on full payment (markPaid → syncProductCatalog). An approved-
but-unpaid PO's items weren't selectable for further POs yet.
- extract syncProductCatalog into lib/product-catalog.ts (shared).
- call it from approvePo so approved items are immediately catalogued (create
product by name if unknown, link the line item, upsert last/per-vendor price);
payment still re-syncs to refresh prices. Idempotent.
- test: approving a PO with a free-text line creates + links the product and
records the per-vendor price.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
