fix: handle UTF-8 BOM in CSV upload to fix KeyError

fix: remove unused jinja2 import from Dockerfile

feat: add reveal answer button for each question during test

feat: Implement admin dashboard for managing tests and users, including test upload and deletion, and user management.

feat: Add UserDashboard page and foundational global styling with theme support.

feat: introduce initial frontend application with user dashboard, admin, and login pages.

feat: implement initial frontend application structure with React, routing, theming, and global styles.

feat: Add JWT-based authentication and authorization module with password hashing.

feat: Establish core backend with user authentication, admin test management, user test taking, and a Dockerfile import fix.

chore: Install frontend dependencies.

initial commit