test: add accessibility tests with jest-axe

[imuniqueshiv]

Description

This PR integrates automated accessibility testing using jest-axe and adds accessibility coverage for key UI components.

Changes Made

• Configured accessibility testing with jest-axe

• Added Vitest accessibility setup (vitest.config.ts and vitest.setup.ts)

• Added accessibility test coverage for:

  • FileUpload
  • PresetSelector
  • FormatSelector
  • ExportSettings

• Fixed accessibility violations detected in FileUpload

  • Added accessible labels for file inputs
  • Removed nested interactive element violations

• Verified all accessibility tests pass successfully

Validation

• All existing tests continue to pass
• Accessibility tests report zero violations
• Total test results: 57/57 passing

Related Issue

Closes #170

Type of Contribution

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

Participant Info

• GitHub username: imuniqueshiv
• Contribution level (Beginner/Intermediate/Advanced): Intermediate

Checklist

• I have read the contribution guidelines
• My changes follow the project structure
• 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

[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
2. ✅ Vercel preview — a preview deployment will be created (requires maintainer authorization for fork PRs)
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.