Move the use-case index onto Learn so the pilot stories stay reachable, and make share images resolve on the host that serves the page.

Co-authored-by: Cursor <cursoragent@cursor.com>

lib/siteMetadata.ts

@@ -153,9 +153,7 @@ export function articleShareImages(
   slug: string,
   alt: string,
 ): ShareImage[] | undefined {
-  if (
-    !(CONTENT_CATALOG_SLUG_ORDER as readonly string[]).includes(slug)
-  ) {
+  if (!(CONTENT_CATALOG_SLUG_ORDER as readonly string[]).includes(slug)) {
     return undefined;
   }
   return [shareImage(contentBlogOgPath(slug), alt)];
@@ -241,15 +239,30 @@ export function routeMetadata(
   };
 }
 
+/**
+ * Link unfurlers. Staging stays out of search indexes, and these agents can
+ * still fetch the page so a shared link can show its image.
+ */
+const UNFURL_USER_AGENTS = [
+  "Twitterbot",
+  "facebookexternalhit",
+  "Slackbot",
+  "Discordbot",
+  "LinkedInBot",
+  "TelegramBot",
+  "WhatsApp",
+  "Bluesky",
+] as const;
+
 export function buildRobots(
   host: string | null | undefined,
 ): MetadataRoute.Robots {
   if (!isIndexableHost(host)) {
     return {
-      rules: {
-        userAgent: "*",
-        disallow: "/",
-      },
+      rules: [
+        { userAgent: "*", disallow: "/" },
+        { userAgent: [...UNFURL_USER_AGENTS], allow: "/" },
+      ],
     };
   }