Add photo galleries API and frontend for public and admin viewing.

Introduces the Go photo-api service, nginx/systemd deploy wiring, and Next.js gallery/lightbox pages so event photos can be managed and browsed.

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

frontend/src/app/(public)/events/[id]/gallery/page.tsx

@@ -0,0 +1,50 @@
+import type { Metadata } from 'next';
+import { Suspense } from 'react';
+import type { PhotoGallery, Photo } from '@/lib/api';
+import GalleryClient from '@/app/(public)/photos/[slug]/GalleryClient';
+
+const photoApiUrl = process.env.PHOTO_API_URL || 'http://localhost:3003';
+
+interface PageProps {
+  params: { id: string }; // event slug, same param name as the parent route
+}
+
+// Public event galleries render server-side; link/ticket galleries return
+// null here and are fetched client-side with the viewer's token.
+async function getEventGallery(
+  eventSlug: string
+): Promise<{ gallery: PhotoGallery; photos: Photo[] } | null> {
+  try {
+    const res = await fetch(
+      `${photoApiUrl}/api/photos/public/events/${encodeURIComponent(eventSlug)}/gallery`,
+      { next: { revalidate: 300 } }
+    );
+    if (!res.ok) return null;
+    return await res.json();
+  } catch {
+    return null;
+  }
+}
+
+export async function generateMetadata({ params }: PageProps): Promise<Metadata> {
+  const data = await getEventGallery(params.id);
+  if (!data) {
+    return { title: 'Event Photos', robots: { index: false } };
+  }
+  return {
+    title: `${data.gallery.title} – Photos`,
+    description:
+      data.gallery.description ||
+      `Photos from ${data.gallery.title}, a Spanglish language exchange event in Asunción.`,
+  };
+}
+
+export default async function EventGalleryPage({ params }: PageProps) {
+  const initial = await getEventGallery(params.id);
+  return (
+    // Suspense boundary required by useSearchParams() in the client child.
+    <Suspense>
+      <GalleryClient eventSlug={params.id} initial={initial} />
+    </Suspense>
+  );
+}