- Add useRealtimeSync hook for polling server updates every 3 seconds
- Create API endpoint to check last updated timestamp for lists
- Integrate real-time sync into ListDetailView component
- Automatically refresh when other users make changes to shared lists
- Poll on interval and when page becomes visible again
- Install next-auth@beta, bcryptjs, zod, and @auth/prisma-adapter
- Create auth.ts with credentials provider and JWT session strategy
- Create auth.config.ts for edge-compatible middleware configuration
- Add NextAuth type extensions for session and JWT
- Create API route handler for authentication
- Configure environment variables for NextAuth
- Add AUTH_SETUP.md documentation
Task: 1. Set up authentication infrastructure
Requirements: 1.1, 2.1
