Missing multipack attribute

When selling multi-unit packs of an identical product (e.g., 4-pack of soda), Google needs the multipack attribute set to the unit count. Without it, ranking suffers.

Feed treats the multipack as a single product without declaring it's actually 4 units of the same SKU.

1. Set multipack to the integer number of identical units (e.g., 4 for a 4-pack).
2. The GTIN should be the multipack's GTIN, not the single-unit GTIN.
3. Don't set multipack=1 — leave blank if it's a single unit.

• Confusing multipack (same product, multiple units) with bundle (different products together)