A stored variant position is a CatalogVariant attribute, not a fields{} entry,
so the serializer emitted an empty Variant Position cell — which re-imports as
'reset to file order'. A non-sequential stored position (a merchant can import
explicit positions) then round-tripped to a spurious update, violating INV-12.
Emit str(variant.position) explicitly (like _write_image). The property-test
generator now assigns non-sequential positions to lock the regression, plus a
targeted test. Also wires isExportEnabled into ProductsPage (was dead code).
Both caught by the final code review.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
ben.stull