Implement User Account and Session Management for Next.js Project

### **Details**
### Feature: User account creation and management.
Purpose: Maintain user sessions for a more seamless experience.
Implementation:
Integrate user authentication (e.g., OAuth, JWT, or a similar approach).
Enable session management using secure methods (e.g., cookies or session storage).
Ensure compatibility with the existing Next.js architecture.

No files, tests, or entry points are named. Start by reviewing the existing Next.js architecture and identifying how user accounts, authentication, and session state currently fit together. Done means implementing a defined account and session flow with a chosen secure authentication approach while preserving compatibility with the existing architecture.

Written by the indexing model from the issue text.