fix: resolve next.js production build compilation errors and worker type mismatches

[thakurakanksha288]

Description

This PR resolves several critical TypeScript compiler errors, ESLint accessibility blocks, and Webpack caching issues that were preventing the production build (npm run build) from completing successfully.

Changes Made

• VideoPreview.tsx: Addressed ESLint jsx-a11y rules for interactive element tracking and matched the framing check to the correct strict "fill" | "fit" types.
• ffmpeg.worker.ts: Implemented a fallback WorkerContext inline interface to bypass missing global DedicatedWorkerGlobalScope types without modifying global configuration scopes.
• constants.ts & frame-export.ts: Unified the recipe data layer by updating legacy rotate property references to the typed rotation field.
• textOverlay.ts: Addressed an optional fallback block by casting the overlay reference dynamically, and mathematically aligned the FFmpeg drawtext coordinates (tw/2, th/2) with the UI's center-origin layout.

Verification

• Wiped the Next.js and Webpack disk caches cleanly.
• Successfully ran npm run build with zero compilation errors.

closes #1409

[vercel]

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[github-actions]

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[github-actions]

👋 Thanks for your PR, @thakurakanksha288!

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

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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)
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Useful links

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Happy coding! 🎉

[thakurakanksha288]

Hi @magic-peach,

Thank you for reviewing my PR. I noticed that the checks are currently showing "5 workflows awaiting approval" and the build status is still pending, while Vercel deployment requires authorization. Since external contributor workflows require maintainer approval, could you please approve the pending GitHub Actions workflows so the remaining checks can run?

Thank you for your time and support.

[thakurakanksha288]

hi @magic-peach , kindly review this

[thakurakanksha288]

hi @magic-peach, kindly merge this under the right labels

[magic-peach]

Hi @thakurakanksha288 — thanks for this, and sorry for the wait.

I'd like to get this merged, but it adds headers() to next.config.ts, which is silently ignored under output: "export".

To get it unblocked:

1. move those headers into vercel.json instead

Could you take a look within the next 14 days? If I don't hear back by then I'll close it to keep the queue manageable — but you're very welcome to reopen it any time after that. Thanks again for contributing to Reframe 🙏

[netlify]

❌ Deploy Preview for reframe-os failed.

Name	Link
🔨 Latest commit	dacd7c3
🔍 Latest deploy log	https://app.netlify.com/projects/reframe-os/deploys/6aa989b6475fed0008867ef2

[magic-peach]

Made the specific fix that was asked for: removed the headers() block from next.config.ts — it's silently ignored under output: "export" anyway, and the same COOP/COEP headers it added already live in vercel.json (and now netlify.toml too), so this was dead code rather than something that needed relocating.

That said, this branch has drifted a long way from current main (a Next.js 16 upgrade and a lot of other work has landed since this was opened) — rebasing now touches 9 files with real conflicts in core logic (ffmpeg.ts, ffmpeg.worker.ts, useVideoEditor.ts, types.ts, text-overlay.ts), several of which look like they may already be fixed independently on main. That needs your own judgment on what's still needed vs. already superseded, not something I should guess at. Would you be up for rebasing onto current main and seeing what's actually left to fix? Happy to review once that's done.