3.5.1: replace deprecated Shopify fields, and show product images

[mksd0398]

Summary

• Four deprecated Shopify fields replaced in both templates. They still work in 2026-10, but a later API version will remove them.

  Deprecated	Replacement
  Product.featuredImage	featuredMedia
  Product.images	media
  ShopPlan.displayName	publicDisplayName
  Shop.billingAddress	shopAddress

  GET /api/shop and GET /api/products/:id return the new names, and the Dashboard and Products pages read them. GET /api/products/search keeps its flat image field.

• Product search cards now show images. The search route returns image as a URL; the page looked for image.src, so every card said "No image".

• Images are requested at display size: 600 pixels for a card, 800 for the detail view. They were the originals, up to 3908 pixels wide.

Released as 3.5.1 when this merges.

Test plan

• New template test, written first: a search result's image comes from its featured media, is null without media or without a preview, and is asked for at a reduced size.
• npm run test:e2e: 58/58. Both templates build and pass their own 49 tests.
• npm run check:graphql: all 6 queries valid against 2026-10, with no deprecated field left.
• Real store: the template's route handlers, with Shopify not stubbed, run against a development store on 2026-10.
  • The shop route returns the plan name and country.
  • Search returns images for 9 of 10 products; the tenth really has no media and returns null.
  • The detail route returns its media list and alt text.
• Both pages loaded in a browser on that real data: the Dashboard shows the plan and country; the Products cards and the detail view show images at 600 and 800 pixels.

🤖 Generated with Claude Code