commercetools product bundles via product selections and custom bundle logic

Verified steps

1. Understand that commercetools does not have a native bundle product type; bundles are typically modeled using a custom product type with references to component products, or via product sets using Product Selections.
2. Create a custom product type for bundles with attributes such as bundleComponents (a set of product references or variant references) and bundleQuantities.
3. When adding a bundle to a cart, add the bundle product as a line item and then add each component as separate line items with custom attributes indicating they are bundle components (e.g., a custom lineItem field bundleParentId).
4. Use a Cart Extension (API Extension) to enforce bundle pricing and component line item consistency server-side on every cart update.
5. Alternatively, use Product Selections to group bundle-eligible products for catalog management, but implement bundle-in-cart logic separately in your application layer.
6. Consult current commercetools documentation for any native bundle or set product patterns that may have been introduced, as the platform evolves continuously.