feat: improve editor panel visual hierarchy and section grouping

[imuniqueshiv]

Description

Improved the visual hierarchy of the editor panel by grouping related controls into clearly separated sections with better spacing, headings, and layout organization.

Changes made

• Grouped editor controls into:

  • Format & Size
  • Timeline
  • Transform
  • Playback
  • Quality & Format
  • Colour
  • Processing

• Improved section hierarchy with clear headings and separators

• Rebalanced desktop layout to reduce empty space and improve scanability

• Preserved mobile single-column responsiveness

• Added a dedicated StabilizationControl component

• Maintained existing functionality and theme consistency using existing CSS tokens

Related Issue

Closes #670

Type of Contribution

• New feature
• GSSoC contribution

Participant Info

• GitHub username: @imuniqueshiv
• Contribution level: Intermediate

Screen Recording

Recording / Loom link:

issue.670.mp4

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

[vercel]

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[github-actions]

👋 Thanks for your PR, @imuniqueshiv!

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

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

What happens next

1. 🤖 Automated checks — build & TypeScript typecheck will run automatically
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3. 👀 Code review — a maintainer will review your changes
4. 🚀 Merge — once approved, your PR will be merged!

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
• ⭐ Star the repo to support the project!

Happy coding! 🎉

[github-actions]

✅ PR Format Check Passed — @imuniqueshiv

Basic format checks passed. A maintainer will review your code changes.

This does not mean the PR is approved — it just means the format is correct.