feat: public API, SEO and existing surfaces

features/site_public_url_pattern.feature

@@ -64,7 +64,8 @@ Feature: Public URL pattern of a site
 
   Scenario: Saving the pattern changes nothing else
     When an owner sets the pattern
-    Then no article, canonical URL or public response changes
+    Then no article is changed and no canonical override is changed
+    And the canonical output and sitemap addresses of the site's articles follow the pattern from then on, as in features/localization_public_api_and_surfaces.feature
     And the site's other fields are unchanged
 
   Scenario: Existing site behaviour is unchanged