Update markdown separator in main function for improved visual clarity

Fix typo in title for the final grade display

modified: app.py

Implement code changes to enhance functionality and improve performance

Update encrypted grades in CSV file to reflect new data format and enhance security measures.

Remove CSV decryption function and related imports; refactor app.py to retrieve student grades directly from a database connection, enhancing data management and security.

Add refresh button to grades display in app.py for improved user experience

Fix variable reference in student ID display within main function of app.py

Refactor database connection parameters to use simplified secret keys for improved clarity and maintainability.

Update database configuration to use simplified secret keys for connection parameters.

Update requirements.txt to include mysql-connector-python and python-dotenv for database connectivity and environment variable management.

Refactor data loading to use MySQL database connection; removed CSV decryption function and implemented student grade retrieval from the database.

modified: app.py

modified: app.py

added grade <= 3.0

updated grade

modified: encrypted_grades.csv

modified: encrypted_grades.csv

modified: app.py