User Authentication

- Add a login and registration system using Flask-Login and Flask-WTF.
- Create roles (e.g., admin, user) with specific permissions
- Admins can edit/delete any post.
- Users can only edit/delete their own posts.

The issue describes adding a login/registration system with Flask-Login and Flask-WTF, plus role-based permissions. Start by examining the existing Flask app structure, likely in app.py or similar, and the SQLAlchemy models for User and Post. Look for where authentication and authorization logic would be integrated, and check if there are existing templates for login/registration. 'Done' means users can log in, register, and permissions enforce admin vs. user actions on posts.

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