Allow users to upload a small logo or image to embed in the center of QR codes.

Acceptance Criteria:

• Image upload functionality
• Image resizing and optimization
• Ensure QR code remains scannable
• Support PNG, JPG, SVG formats
• Preview with embedded logo

Implementation Hints:

• Use PIL (Python) for image processing
• Implement file upload in frontend
• Validate image dimensions and file size
• Test QR code scannability with embedded images