Feat : QR Code Generator & Scanner implementation

### Project slug (e.g., snake, todo)

qr-code-generator-scanner

### Summary

Implement a QR Code Generator and Scanner feature that allows users to easily create and scan QR codes directly within the app.
This functionality can be useful for sharing links, data, or room details quickly.

### Details / Acceptance criteria

Add an input field where users can enter text or URLs to generate a QR code.
Use a library like qrcode.react (for React) to generate the QR code dynamically.
Implement QR code scanning using the device camera (e.g., react-qr-reader).
Display scanned text or URL below the scanner in real-time.
Ensure mobile responsiveness and intuitive UI design.

Additional Notes:

Keep UI minimal and consistent with the app’s theme.
Optional: Add a download button for saving the generated QR code image.

### Scope

- [x] UI changes
- [x] Logic changes
- [ ] Accessibility
- [ ] Tests (manual)