Add Drag and drop feature for upload

[ambujraj]

What does this PR do?

This adds drag and drop feature along with view selected dialog that shows selected files that can also be removed from dialog.

Issue

Fixes #131

What changed?

• Added Drag and drop feature
• Added View Selected files dialog
• Added folder upload support on drag and drop

Why these changes?

• To simplify the users upload experience.
• Its an enhancement.

Is it tested?

Yes, locally

Checklist

• [x] I have read through the Contributing Guidelines
• [x] I have also updated the dependent codes as well and README.md if applicable
• [x] My code adheres to consistent formatting standards and includes clear comments where necessary to enhance readability and understanding.