test: add demo video regression coverage

[kimberlydemaio]

Why this change?

Issue #68 requests a regression test for the /demo-video page so future changes don't accidentally break the video, captions, poster, or demo link.

Closes #68

What changed?

Added a new unit test for the /demo-video page.

• an HTML5 video element is rendered
• the video source points to /media/codeverse-demo.mp4
• the poster references /media/codeverse-demo-poster.jpg
• an English captions track points to /media/codeverse-demo.vtt
• the captions track is not marked as default
• the page includes a link to the interactive /demo workspace

No production code was changed.

How did you verify it?

• Relevant unit or server tests
• npm run lint
• npm run typecheck
• npm run audit:repo
• Relevant application or catalog audits
• Production build when the client changed
• Screenshots or recording for visible UI changes

Ran npx vitest run tests/unit/demo-video.test.tsx

All 6 tests passed.

Risk, rollout, and recovery

Low risk. This is a test-only change, so it shouldn't affect the application.

If needed, it can be reverted by removing the new test file.

Reviewer guide

Please review:

• client/tests/unit/demo-video.test.tsx
• whether the six assertions accurately cover the requirements in issue [First PR] Add a regression test for the narrated demo player #68
• whether the selectors and expectations match the existing testing conventions in the client test suite

[vercel]

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[Ayush-Kumar0207]

Hi Kimberly — thank you for picking this up, and sorry I left your first contribution waiting for a week. I’ve reviewed the test, and it’s exactly the focused regression coverage this issue needed: it protects the video source, poster, optional captions behavior, and interactive demo link without changing production code.

I’ve approved the first-time-contributor workflows now and I’m watching the checks. If they stay green, I’ll get this merged promptly. I also appreciate how clearly you documented the change and verification — this is a strong first contribution to CodeVerse.

[Ayush-Kumar0207]

Approved — this is focused, well documented, and covers every acceptance criterion from #68. Thank you for keeping it test-only and following the existing testing conventions.

[Ayush-Kumar0207]

Merged — all refreshed CI, container, and CodeQL checks passed. Thank you again, Kimberly. This was a careful and genuinely useful first contribution, and you’d be very welcome to contribute again whenever another issue interests you.