feat: public API, SEO and existing surfaces

features/site_public_url_pattern.qa.md

@@ -10,6 +10,7 @@ Accepted together with features/site_public_url_pattern.feature.
 
 ## Automated, SQLite file (task test)
 
+3b. Saving the pattern changes no article and no canonical override; the canonical output and sitemap addresses follow the pattern afterwards (features/localization_public_api_and_surfaces.qa.md, items 5 and 6).
 4. The column migration is covered in the site_languages QA step 5. Round-trip a pattern of 512 characters and refuse 513.
 
 ## Automated (Vitest + Vue Test Utils, task test:web)