fix(seo): canonical self-deindexing on /docs/*, truthful llms.txt, real sitemap dates, RSS feed, breadcrumbs, per-article OG images

- /docs subpages canonicalized to /docs and had no descriptions; each now
  uses pageMetadata with its own path (was: Google could index at most one)
- llms.txt claimed Team EUR 149, RBAC/SLA and BYO-cloud that do not exist;
  regenerated from lib/seo.ts truth + new llms-full.txt with docs content
- sitemap stamped lastModified=now on every request; now real per-route dates
  from new lib/articles.ts registry (single source for guides index/sitemap/RSS)
- new /feed.xml RSS 2.0 route + alternates link in root layout
- articleJsonLd: image (per-guide opengraph-image via lib/og-article.tsx),
  Person author, wordCount; new breadcrumbJsonLd on guides + docs
- GSC verification via NEXT_PUBLIC_GSC_VERIFICATION (documented in .env.example)
- dropped fabricated Enterprise EUR 499 offer from SoftwareApplication JSON-LD
- article-shell: OL/Table/Note primitives for upcoming articles

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01SXUwmPVRTD8AKQtio6gCN5

apps/web/app/layout.tsx

@@ -26,7 +26,15 @@ export const metadata: Metadata = {
   authors: [{ name: SITE_NAME }],
   creator: SITE_NAME,
   publisher: SITE_NAME,
-  alternates: { canonical: '/' },
+  alternates: {
+    canonical: '/',
+    types: { 'application/rss+xml': [{ url: '/feed.xml', title: `${SITE_NAME} — MCP guides` }] },
+  },
+  // Google Search Console ownership token. Unset in dev; set in production so
+  // the sitemap can be submitted and indexing monitored.
+  ...(process.env.NEXT_PUBLIC_GSC_VERIFICATION
+    ? { verification: { google: process.env.NEXT_PUBLIC_GSC_VERIFICATION } }
+    : {}),
   openGraph: {
     type: 'website',
     locale: 'en_US',