fix: configure PostgreSQL for production and clean up deployment

- Fix database configuration to use PostgreSQL in production
- Add knexfile.js to support both SQLite (dev) and PostgreSQL (prod)
- Create admin user creation script (scripts/create-admin.js)
- Clean up docker-compose files:
  - Remove redundant docker-compose.yml and docker-compose.local.yml
  - Create docker-compose.dev.yml for development
  - Update docker-compose.prod.yml with proper DB configuration
- Clean up environment files:
  - Update .env.example for development
  - Update .env.production.example with proper settings
  - Remove redundant .env.local
- Update backend .env.example with database configuration options
- Create comprehensive DEPLOYMENT.md with admin setup instructions
- Fix production database name consistency (picpeak instead of photoapp)

docker-compose.dev.yml

@@ -0,0 +1,61 @@
+# Development Docker Compose Configuration
+version: '3.8'
+
+services:
+  backend:
+    build: 
+      context: ./backend
+      dockerfile: Dockerfile
+    ports:
+      - "3001:3000"
+    environment:
+      - NODE_ENV=development
+      - PORT=3000
+      - JWT_SECRET=dev-secret-change-in-production
+      - ADMIN_URL=http://localhost:3005
+      - FRONTEND_URL=http://localhost:3005
+      - DATABASE_CLIENT=sqlite3
+      - DATABASE_PATH=./data/photo_sharing.db
+      # Email - uses Mailhog
+      - SMTP_HOST=mailhog
+      - SMTP_PORT=1025
+      - SMTP_SECURE=false
+      - EMAIL_FROM=noreply@photo-sharing.local
+    volumes:
+      - ./backend:/app
+      - /app/node_modules
+      - ./storage:/app/storage
+      - ./data:/app/data  
+      - ./logs:/app/logs
+    depends_on:
+      - mailhog
+    command: sh -c "npm install && npm run dev"
+    healthcheck:
+      test: ["CMD", "wget", "--quiet", "--tries=1", "--spider", "http://localhost:3000/api/health"]
+      interval: 30s
+      timeout: 10s
+      retries: 3
+
+  frontend:
+    build:
+      context: ./frontend
+      dockerfile: Dockerfile
+    ports:
+      - "3005:80"
+    environment:
+      - NODE_ENV=development
+    volumes:
+      - ./frontend/nginx.conf:/etc/nginx/conf.d/default.conf:ro
+    depends_on:
+      - backend
+    healthcheck:
+      test: ["CMD", "curl", "-f", "http://localhost/health"]
+      interval: 30s
+      timeout: 10s
+      retries: 3
+
+  mailhog:
+    image: mailhog/mailhog:latest
+    ports:
+      - "1025:1025"  # SMTP
+      - "8025:8025"  # Web UI