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/hooks/useComparison.ts

@@ -0,0 +1,87 @@
+/**
+ * Custom hook for managing school comparison state
+ */
+
+'use client';
+
+import { useState, useEffect, useCallback } from 'react';
+import useSWR from 'swr';
+import { fetcher } from '@/lib/api';
+import { getFromLocalStorage, setToLocalStorage } from '@/lib/utils';
+import type { School, ComparisonResponse } from '@/lib/types';
+
+const STORAGE_KEY = 'selectedSchools';
+const MAX_SCHOOLS = 5;
+
+export function useComparison() {
+  const [selectedSchools, setSelectedSchools] = useState<School[]>([]);
+  const [isInitialized, setIsInitialized] = useState(false);
+
+  // Load from localStorage on mount
+  useEffect(() => {
+    const stored = getFromLocalStorage<School[]>(STORAGE_KEY, []);
+    setSelectedSchools(stored);
+    setIsInitialized(true);
+  }, []);
+
+  // Save to localStorage when schools change
+  useEffect(() => {
+    if (isInitialized) {
+      setToLocalStorage(STORAGE_KEY, selectedSchools);
+    }
+  }, [selectedSchools, isInitialized]);
+
+  // Fetch comparison data for selected schools
+  const urns = selectedSchools.map((s) => s.urn).join(',');
+  const { data, error, isLoading, mutate } = useSWR<ComparisonResponse>(
+    selectedSchools.length > 0 ? `/compare?urns=${urns}` : null,
+    fetcher,
+    {
+      revalidateOnFocus: false,
+      dedupingInterval: 10000, // 10 seconds
+    }
+  );
+
+  const addSchool = useCallback((school: School) => {
+    setSelectedSchools((prev) => {
+      // Check if already selected
+      if (prev.some((s) => s.urn === school.urn)) {
+        return prev;
+      }
+
+      // Check max limit
+      if (prev.length >= MAX_SCHOOLS) {
+        alert(`Maximum ${MAX_SCHOOLS} schools can be compared`);
+        return prev;
+      }
+
+      return [...prev, school];
+    });
+  }, []);
+
+  const removeSchool = useCallback((urn: number) => {
+    setSelectedSchools((prev) => prev.filter((s) => s.urn !== urn));
+  }, []);
+
+  const clearAll = useCallback(() => {
+    setSelectedSchools([]);
+  }, []);
+
+  const isSelected = useCallback(
+    (urn: number) => selectedSchools.some((s) => s.urn === urn),
+    [selectedSchools]
+  );
+
+  return {
+    selectedSchools,
+    comparisonData: data?.comparison,
+    isLoading,
+    error,
+    addSchool,
+    removeSchool,
+    clearAll,
+    isSelected,
+    canAddMore: selectedSchools.length < MAX_SCHOOLS,
+    mutate,
+  };
+}