Make next event visible to AI crawlers (SSR, JSON-LD, meta, llms.txt)

- SSR next event on homepage; pass initialEvent from server to avoid client-only content
- Add schema.org Event JSON-LD on homepage when next event exists
- Dynamic homepage metadata (description, OG, Twitter) with next event date
- Add dynamic /llms.txt route for AI-friendly plain-text event info
- Revalidation: support next-event tag; backend revalidates sitemap + next-event on event CUD
- Allow /llms.txt in robots.txt

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

frontend/src/app/(public)/page.tsx

@@ -1,3 +1,4 @@
+import type { Metadata } from 'next';
 import HeroSection from './components/HeroSection';
 import NextEventSectionWrapper from './components/NextEventSectionWrapper';
 import AboutSection from './components/AboutSection';
@@ -5,13 +6,157 @@ import MediaCarouselSection from './components/MediaCarouselSection';
 import NewsletterSection from './components/NewsletterSection';
 import { getCarouselImages } from '@/lib/carouselImages';
 
-export default function HomePage() {
+const siteUrl = process.env.NEXT_PUBLIC_SITE_URL || 'https://spanglish.com.py';
+const apiUrl = process.env.NEXT_PUBLIC_API_URL || 'http://localhost:3001';
+
+interface NextEvent {
+  id: string;
+  title: string;
+  titleEs?: string;
+  description: string;
+  descriptionEs?: string;
+  shortDescription?: string;
+  shortDescriptionEs?: string;
+  startDatetime: string;
+  endDatetime?: string;
+  location: string;
+  locationUrl?: string;
+  price: number;
+  currency: string;
+  capacity: number;
+  status: 'draft' | 'published' | 'cancelled' | 'completed' | 'archived';
+  bannerUrl?: string;
+  externalBookingEnabled?: boolean;
+  externalBookingUrl?: string;
+  availableSeats?: number;
+  bookedCount?: number;
+  isFeatured?: boolean;
+  createdAt: string;
+  updatedAt: string;
+}
+
+async function getNextUpcomingEvent(): Promise<NextEvent | null> {
+  try {
+    const response = await fetch(`${apiUrl}/api/events/next/upcoming`, {
+      next: { tags: ['next-event'] },
+    });
+    if (!response.ok) return null;
+    const data = await response.json();
+    return data.event || null;
+  } catch {
+    return null;
+  }
+}
+
+// Dynamic metadata with next event date for AI crawlers and SEO
+export async function generateMetadata(): Promise<Metadata> {
+  const event = await getNextUpcomingEvent();
+
+  if (!event) {
+    return {
+      title: 'Spanglish – Language Exchange Events in Asunción',
+      description:
+        'Practice English and Spanish at relaxed social events in Asunción. Meet locals and internationals. Join the next Spanglish meetup.',
+    };
+  }
+
+  const eventDate = new Date(event.startDatetime).toLocaleDateString('en-US', {
+    weekday: 'long',
+    year: 'numeric',
+    month: 'long',
+    day: 'numeric',
+  });
+
+  const description = `Next event: ${eventDate} – ${event.title}. Practice English and Spanish at relaxed social events in Asunción. Meet locals and internationals.`;
+
+  return {
+    title: 'Spanglish – Language Exchange Events in Asunción',
+    description,
+    openGraph: {
+      title: 'Spanglish – Language Exchange Events in Asunción',
+      description,
+      url: siteUrl,
+      siteName: 'Spanglish',
+      type: 'website',
+      images: [
+        {
+          url: event.bannerUrl
+            ? event.bannerUrl.startsWith('http')
+              ? event.bannerUrl
+              : `${siteUrl}${event.bannerUrl}`
+            : `${siteUrl}/images/og-image.jpg`,
+          width: 1200,
+          height: 630,
+          alt: `Spanglish – ${event.title}`,
+        },
+      ],
+    },
+    twitter: {
+      card: 'summary_large_image',
+      title: 'Spanglish – Language Exchange Events in Asunción',
+      description,
+    },
+  };
+}
+
+function generateNextEventJsonLd(event: NextEvent) {
+  return {
+    '@context': 'https://schema.org',
+    '@type': 'Event',
+    name: event.title,
+    description: event.shortDescription || event.description,
+    startDate: event.startDatetime,
+    endDate: event.endDatetime || event.startDatetime,
+    eventAttendanceMode: 'https://schema.org/OfflineEventAttendanceMode',
+    eventStatus:
+      event.status === 'cancelled'
+        ? 'https://schema.org/EventCancelled'
+        : 'https://schema.org/EventScheduled',
+    location: {
+      '@type': 'Place',
+      name: event.location,
+      address: {
+        '@type': 'PostalAddress',
+        addressLocality: 'Asunción',
+        addressCountry: 'PY',
+      },
+    },
+    organizer: {
+      '@type': 'Organization',
+      name: 'Spanglish',
+      url: siteUrl,
+    },
+    offers: {
+      '@type': 'Offer',
+      price: event.price,
+      priceCurrency: event.currency,
+      availability:
+        (event.availableSeats ?? 0) > 0
+          ? 'https://schema.org/InStock'
+          : 'https://schema.org/SoldOut',
+      url: `${siteUrl}/events/${event.id}`,
+    },
+    image: event.bannerUrl || `${siteUrl}/images/og-image.jpg`,
+    url: `${siteUrl}/events/${event.id}`,
+  };
+}
+
+export default async function HomePage() {
   const carouselImages = getCarouselImages();
+  const nextEvent = await getNextUpcomingEvent();
 
   return (
     <>
+      {nextEvent && (
+        <script
+          type="application/ld+json"
+          dangerouslySetInnerHTML={{
+            __html: JSON.stringify(generateNextEventJsonLd(nextEvent)),
+          }}
+        />
+      )}
       <HeroSection />
-      <NextEventSectionWrapper />
+      <NextEventSectionWrapper initialEvent={nextEvent} />
       <AboutSection />
       <MediaCarouselSection images={carouselImages} />
       <NewsletterSection />