Sizes and variants

In the product editor, the Sizes area holds your variants — Small / Large, Half Tray / Full Tray, 6-piece / 12-piece. Each size is its own sellable thing:

• •Its own price — a full tray isn't 2× a half tray unless you say so.
• •A serves range — "serves 4–6" on a tray answers the customer's real question and lifts catering-size orders.
• •Its own order — arrange sizes smallest to largest (or lead with the one you want picked).

On the menu, the product shows its starting price and size count; customers pick the size when they order. There's no per-size out-of-stock toggle today — if you run out of just one size, mark the whole item out of stock (or remove that size) until you're restocked.