feat: add global drag-and-drop upload overlay

[Ram-sah19]

Description

Implemented a global drag-and-drop upload experience for the VideoEditor screen.

Previously, users could only upload videos through the dedicated FileUpload component. This update introduces a full-screen drag-and-drop overlay that appears whenever a video file is dragged anywhere over the editor window.

Changes Made

• Added a global drag state using:

const [isDraggingGlobally, setIsDraggingGlobally] = useState(false);

• Added root-level onDragEnter handling in VideoEditor.tsx

• Implemented a full-screen drag-and-drop overlay with:

  • Frosted glass effect (backdrop-blur-sm)
  • Dashed upload border
  • Animated upload prompt
  • Centered “Drop video here to begin” UI

• Added:

  • onDragOver
  • onDragLeave
  • onDrop
    event handling for smooth drag interaction

• Connected dropped files directly to the existing:

handleFileSelect(file)

workflow

This improves usability and creates a more modern editor-style upload experience.

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Related Issue

Closes #748

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Type of Contribution

• Bug fix
• New feature
• Documentation update
• GSSoC contribution

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Participant Info

• GitHub username: @Ram-sah19
• Contribution level: Intermediate

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Screenshot

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Checklist

• I have read the contribution guidelines
• My changes follow the project structure
• I have tested my changes in Chrome, Firefox, and Safari
• bun run lint passes (no ESLint errors)
• bunx tsc --noEmit passes (no TypeScript errors)
• New interactive elements have aria-label / accessible names
• No console.log statements left in
• This PR is related to a valid issue
• Screen recording attached above

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[github-actions]

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[github-actions]

👋 Thanks for your PR, @Ram-sah19!

Welcome to Reframe — a browser-based video editor built for everyone 🎬

🟠 GSSoC'26 PR detected — thanks for contributing under GirlScript Summer of Code 2026!

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Quick checklist

• PR title follows Conventional Commits (e.g. feat: add dark mode)
• Linked the issue this PR closes (e.g. Closes #123)
• Tested the changes locally (bun run dev)
• Build passes (bun run build)

Useful links

• 📖 CONTRIBUTING.md
• 🐛 Open Issues
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Happy coding! 🎉