Architect — F-015 SEO core: structured data, sitemap, redirects

Feature

F-015 adds SEO crawlability and structured data to the existing F-014 storefront catalog pages.

Create a small storefront SEO module under project/storefront/src/lib/seo/:

json-ld.ts builds typed JSON-LD objects for Organization, BreadcrumbList and Product.
redirects.ts defines a RedirectRepository interface and an env-backed implementation.
Keep public URL generation centralized through existing absoluteUrl() / SITE_URL.

No new runtime dependency is required.

Root layout embeds Organization JSON-LD once.
Product pages embed:
- Product JSON-LD using product name, description, canonical URL and main image when available.
- BreadcrumbList JSON-LD for Home → Product.
Category and brand pages embed BreadcrumbList JSON-LD.
JSON-LD is rendered as application/ld+json with JSON serialization, not string concatenation.

Use Next.js metadata routes:

Sitemap source:

Static public URLs: /, /products/search.
Product URLs from searchProducts({ limit: 100, offset }), which returns active products only through backend SearchProducts.activeOnly = true; page through results to avoid silently truncating the first page.
Category URLs from listCategoryTree() flattened recursively.
Brand URLs from a new public GET /brands backend endpoint and storefront listBrands() client helper.
On API failure, sitemap degrades to static URLs rather than failing the build.

Add src/middleware.ts using an env-backed redirect store.
RedirectRepository.findBySourcePath(pathname) returns a redirect target when configured.
Configure redirects with REDIRECTS_JSON, an array of { "from": "/old", "to": "/new" } entries.
Middleware returns permanent 301 redirects only for same-origin local paths. External targets are rejected by the parser to avoid open redirects.
Redirect source and target paths must start with /; source cannot equal target.

Extend the brands module minimally:

Add BrandRepository.list().
Add ListBrands use case.
Add public GET /brands returning { items: [...] } in stable name ASC, id ASC order.

Product JSON-LD: product page embeds Product schema script.
Sitemap: lists active product URLs via search API, category URLs, brand URLs and static pages; draft products excluded by backend active search.
Redirect: middleware redirects stored old path with HTTP 301 to same-origin local target.
Canonical URLs: existing F-014 canonical metadata remains on product/category/brand/search and root layout gains canonical metadata.
verify.sh: must pass after gates.

No hreflang and no external SEO tooling by scope.
Lighthouse/Google validator may be unavailable locally; validate structurally and through build output.
Env redirects are enough for this slice; a database-backed admin UI is intentionally deferred.