Add nginx reverse proxy and environment configuration

- Add nginx.conf for proxying API requests to backend
- Update frontend Dockerfile for production build with nginx
- Move hardcoded values to .env variables in docker-compose.yml
- Add .env.example template for configuration

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

docker-compose.yml

@@ -3,16 +3,16 @@ services:
     image: postgres:16-alpine
     container_name: anime-quiz-db
     environment:
-      POSTGRES_USER: animequiz
-      POSTGRES_PASSWORD: animequiz123
-      POSTGRES_DB: animequiz
+      POSTGRES_USER: ${POSTGRES_USER}
+      POSTGRES_PASSWORD: ${POSTGRES_PASSWORD}
+      POSTGRES_DB: ${POSTGRES_DB}
     volumes:
       - postgres_data:/var/lib/postgresql/data
     ports:
-      - "5432:5432"
+      - "${DB_PORT}:5432"
     restart: unless-stopped
     healthcheck:
-      test: ["CMD-SHELL", "pg_isready -U animequiz"]
+      test: ["CMD-SHELL", "pg_isready -U ${POSTGRES_USER}"]
       interval: 10s
       timeout: 5s
       retries: 5
@@ -22,15 +22,20 @@ services:
       context: ./backend
       dockerfile: Dockerfile
     container_name: anime-quiz-backend
-    ports:
-      - "8000:8000"
     volumes:
       - ./output:/app/output
     env_file:
       - .env
     environment:
-      - QUIZ_OUTPUT_PATH=/app/output/videos
-      - DATABASE_URL=postgresql+asyncpg://animequiz:animequiz123@db:5432/animequiz
+      - DATABASE_URL=${DATABASE_URL}
+      - S3_ENDPOINT=${S3_ENDPOINT}
+      - S3_ACCESS_KEY=${S3_ACCESS_KEY}
+      - S3_SECRET_KEY=${S3_SECRET_KEY}
+      - S3_REGION=${S3_REGION}
+      - S3_BUCKET=${S3_BUCKET}
+      - OUTPUT_PATH=${OUTPUT_PATH}
+      - TEMP_PATH=${TEMP_PATH}
+      - CACHE_PATH=${CACHE_PATH}
     depends_on:
       db:
         condition: service_healthy
@@ -48,11 +53,11 @@ services:
       dockerfile: Dockerfile
     container_name: anime-quiz-frontend
     ports:
-      - "5173:5173"
+      - "${APP_PORT}:80"
+    volumes:
+      - ./nginx/nginx.conf:/etc/nginx/conf.d/default.conf:ro
     depends_on:
       - backend
-    environment:
-      - VITE_API_URL=http://backend:8000
     restart: unless-stopped
 
 volumes: