chore: grounwork for SEO features

docs/design/screens/integration.md

@@ -108,3 +108,9 @@ New section "Images and variants" on the Integration page, after Media and befor
 ## Pass 2 notes
 - The base URL field and the image URL builder output are CodeSnippets with a single tab.
 - Page padding 24 px (16 px on mobile), page title 20/28, section headings 18/26, card titles 15/24, sub headings 14/22 (foundations.md).
+
+## Search and sharing (SEO round)
+New group "Search and sharing" after Articles, in the sidebar index and the mobile Jump to select. Two cards in the existing endpoint style (collapsed, method badge, auth badge "Public", example, 401 and 404 rows, copy buttons):
+- GET /v1/article/{id}/seo: the resolved SEO object. Fields: title, description, canonical_url, robots, og{type,title,description,url,site_name,image,image_alt,locale}, twitter{card,title,description,image,image_alt}, image{url,alt,source}, authors[{name,url,same_as}], published_at, modified_at, fallbacks, json_ld. Drafts answer 404 to anonymous callers.
+- GET /v1/site/{key}/sitemap?page=&size=: yes, shown per site by key. Items: { url, modified_at, noindex }. Total in X-Total-Count. Sizes 25, 50, 100, 500, default 100. 404 "Site not found".
+PATCH /v1/article/{id} lists the new optional fields (slug, excerpt, seo_title, seo_description, cover_image_id, cover_image_alt, social_title, social_description, social_image_id, canonical_url, noindex, seo_dismissed). The 403 row of the HTTP status table adds: site SEO defaults are owner only; article SEO fields need only the right to edit the article.