Act as a senior full-stack developer with 5+ years of experience in real-time applications. Guide me step-by-step in building a real-time chat application using Socket.io, [FRAMEWORK_NAME] for the frontend, and [BACKEND_TECH] for the server. Include best practices for handling [SPECIFIC_FEATURE] like message encryption or user authentication. Provide code snippets, explain key concepts like event emitters and listeners, and troubleshoot common pitfalls such as connection drops or scalability issues. Ensure the tutorial is beginner-friendly but covers advanced topics like room management or WebSocket fallbacks.