Add-on: MV Forged 3PC Center Finish — 2Tone Brush/Polish (per wheel)

Hidden add-on line item. Added automatically to the cart once per wheel when a customer selects a 2Tone (Brush/Polish) finish on the 3PC centers of a 3-Piece wheel. Hidden from the storefront on purpose: it has no images, no collection and is not meant to be found or bought on its own. Its price here is the single source of truth — editing it in admin updates both the price shown on the wheel page and the amount actually charged at checkout, with no code change. Do not rename the handle — the wheel template looks this product up by handle, and renaming it silently drops the upcharge from the configurator.