Feature update

[KTS-o7]

This pull request includes significant updates to the application, focusing on refactoring the data handling from CSV to JSON, adding user management features, and updating the frontend to accommodate these changes. The most important changes include the migration of data storage, the addition of user management routes, and updates to the HTML and CSS files to reflect these changes.

Data Handling and Storage:

• Migrated data storage from CSV to JSON format for both streak data and user data. (app.py, config.py, data/streaks.json, data/users.json) [1] [2] [3] [4]

User Management:

• Added routes and functions to handle adding and deleting users. (app.py)
• Updated the index function to dynamically load and display users. (app.py)

Frontend Updates:

• Updated the HTML template to include forms for adding and deleting users, and to display user-specific data. (templates/index.html)
• Modified CSS to improve layout and styling for the new user management features. (static/css/styles.css) [1] [2]

[KTS-o7]

@kawasthi04 requesting code review