Update Profile Screen with Real Values

## Description:
The profile screen currently displays placeholder values for user information. We need to update the profile screen to fetch and display the real user data from the backend.

## Requirements:
- Fetch user data from the backend (e.g., username, email, profile picture, and any other relevant information).
- Display the real values on the profile screen.
- Ensure the values are updated dynamically if the user makes changes to their profile (e.g., updating profile picture or email).
- Add error handling in case the data cannot be fetched from the backend.

## Acceptance Criteria:
- The profile screen displays the actual user data (username, email, profile picture, etc.).
- If the user updates their profile, the changes should reflect in real-time.
- In case of data fetching errors, an appropriate error message is displayed.