hydrogen-developmentlisted

# Hydrogen Development Own the framework-specific implementation of a Shopify Hydrogen storefront. Keep Shopify as the commerce authority and preserve the accepted boundary from `headless-shopify`; this skill does not replace it. ## Start from the installed project Read repository instructions, package scripts and lockfile, route structure, environment-variable names without printing values, deployed runtime, and the existing cart, session, customer-account, SEO, analytics, and test contracts. When present, also inspect the GraphQL configuration, generated API types, React Router configuration, and runtime entry point. They describe the installed application's contract; do not recreate a current skeleton layout inside an older or custom project. Classify the task before editing: - **New app:** use the current official Hydrogen generator only after the destination and development authorization are clear. - **Existing app:** preserve its installed Hydrogen and React Router contract; do not migrate it merely because a newer preview or scaffold exists. - **Developer preview:** treat the framework-agnostic Hydrogen preview as a separate migration decision, not an upgrade of the current framework. For a new storefront, read [New storefront start](references/new-storefront-start.md). It separates a disposable Mock.shop quickstart from a real-store link and an Oxygen preview deployment; those are not interchangeable steps. For a new headless decision, migration, API/token