Simplified .glb → .drc Workflow: Upload, Compress, Preview, Download

[astyashish]

This PR introduces an easy-to-use UI tool for converting .glb files into .drc format with built-in compression options. The interface is designed for beginners who want to quickly test 3D model compression without using complex command-line tools. Users can upload their .glb file, choose between predefined compression percentages, preview both the original and compressed models side by side, and then download the resulting .drc file. This makes it simple to compare quality versus size trade-offs in real time, helping developers and designers speed up their workflow.

Key Features:

1. Upload .glb files through the browser.
2. Choose compression level (50% or 80%).
3. Convert .glb → .drc instantly.
4. Preview before/after models within the same page.
5. Download the compressed .drc file with one click.

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