Complete Next.js migration with SSR and Docker deployment

- Migrate from vanilla JavaScript SPA to Next.js 16 with App Router
- Add server-side rendering for all pages (Home, Compare, Rankings)
- Create individual school pages with dynamic routing (/school/[urn])
- Implement Chart.js and Leaflet map integrations
- Add comprehensive SEO with sitemap, robots.txt, and JSON-LD
- Set up Docker multi-service architecture (PostgreSQL, FastAPI, Next.js)
- Update CI/CD pipeline to build both backend and frontend images
- Fix Dockerfile to include devDependencies for TypeScript compilation
- Add Jest testing configuration
- Implement performance optimizations (code splitting, caching)

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

nextjs-app/app/sitemap.ts

@@ -0,0 +1,54 @@
+/**
+ * Dynamic Sitemap Generation
+ * Generates sitemap with all school pages and main routes
+ */
+
+import { MetadataRoute } from 'next';
+import { fetchSchools } from '@/lib/api';
+
+const BASE_URL = 'https://schoolcompare.co.uk';
+
+export default async function sitemap(): Promise<MetadataRoute.Sitemap> {
+  // Static pages
+  const staticPages: MetadataRoute.Sitemap = [
+    {
+      url: BASE_URL,
+      lastModified: new Date(),
+      changeFrequency: 'daily',
+      priority: 1.0,
+    },
+    {
+      url: `${BASE_URL}/compare`,
+      lastModified: new Date(),
+      changeFrequency: 'weekly',
+      priority: 0.8,
+    },
+    {
+      url: `${BASE_URL}/rankings`,
+      lastModified: new Date(),
+      changeFrequency: 'weekly',
+      priority: 0.8,
+    },
+  ];
+
+  // Fetch all schools (in batches if necessary)
+  try {
+    const schoolsData = await fetchSchools({
+      page: 1,
+      page_size: 10000, // Fetch all schools
+    });
+
+    const schoolPages: MetadataRoute.Sitemap = schoolsData.schools.map((school) => ({
+      url: `${BASE_URL}/school/${school.urn}`,
+      lastModified: new Date(),
+      changeFrequency: 'monthly',
+      priority: 0.6,
+    }));
+
+    return [...staticPages, ...schoolPages];
+  } catch (error) {
+    console.error('Failed to generate sitemap:', error);
+    // Return just static pages if school fetch fails
+    return staticPages;
+  }
+}