Sync Sellable BoMs

Links each tea variant to its bulk blend for inventory tracking

What this does: Creates Bills of Materials connecting each sellable tea size (2oz, 4oz, etc.) to its bulk blend. When a customer orders a 4oz Berry Focused, Odoo will automatically deduct 4oz from Berry Focused Bulk inventory. Safe to re-run — only creates what's missing, skips everything that already has a BoM.