[w3c-capture-all-screens] Add type definitions for capture all screens.

[paulinagacek]

Context

This PR creates a new package to provide type definitions for Capture All Screens API in line with the specification. Capture All Screens is a part of Isolated Web App APIs.

IWA Explainer: https://github.com/WICG/isolated-web-apps

Motivation

Currently, TypeScript has no knowledge of these IWA-specific APIs. This leads to:

• Lack of Type Safety: Developers are forced to use any or incomplete local interface merging.
• Poor Developer Experience: No autocomplete or inline documentation for these APIs in editors.
• Maintenance Overhead: Projects (like the official IWA Sink) currently rely on hardcoded types that drift out of sync with the implementation.

[typescript-bot]

@paulinagacek Thank you for submitting this PR!

This is a live comment that I will keep updated.

1 package in this PR

• w3c-capture-all-screens (new!) — on npm, on unpkg
  • 3 added owners: ✎@paulinagacek, @GrapeGreen, @shangl

Code Reviews

This PR adds a new definition, so it needs to be reviewed by a DT maintainer before it can be merged.

You can test the changes of this PR in the Playground.

Status

• ✅ No merge conflicts
• ✅ Continuous integration tests have passed
• ✅ Only a DT maintainer can approve changes when there are new packages added

All of the items on the list are green. To merge, you need to post a comment including the string "Ready to merge" to bring in your changes.

---

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[typescript-bot]

🔔 @paulinagacek — you're the only owner, but it would still be good if you find someone to review this PR in the next few days, otherwise a maintainer will look at it. (And if you do find someone, maybe even recruit them to be a second owner to make future changes easier...)

[paulinagacek]

@sheetalkamat could you please take a look? :)

[paulinagacek]

@jakebailey could you please take a look? 🙏🏼 🥺

[paulinagacek]

@jakebailey could you please take a look? 🙏🏼 🥺

@jakebailey I cannot merge this PR without maintainer approval, I think this PR somehow got lost in your dashboard. I would be extremely grateful if you could take a look, thanks!

[typescript-bot]

Re-ping @«anyone?»:

This PR has been out for over a week, yet I haven't seen any reviews.

Could someone please give it some attention? Thanks!

[paulinagacek]

@sheetalkamat @jakebailey kind reminder

[typescript-bot]

It has been more than two weeks and this PR still has no reviews.

I'll bump it to the DT maintainer queue. Thank you for your patience, @paulinagacek.

(Ping @«anyone?».)

[jakebailey]

This package is not intended to be imported as w3c-capture-all-screens; why does it have an export? Shouldn't it be entirely globals?

[paulinagacek]

Right, thank you! Fixed. I've removed the exports and the declare global wrappers. The definitions are now entirely global, and I've updated the tests to reflect this (no imports required).

[typescript-bot]

@jakebailey, @GrapeGreen Thank you for reviewing this PR! The author has pushed new commits since your last review. Could you take another look and submit a fresh review?

[typescript-bot]

@paulinagacek: Everything looks good here. I am ready to merge this PR (at 1fc3cc1) on your behalf whenever you think it's ready.

If you'd like that to happen, please post a comment saying:

Ready to merge

and I'll merge this PR almost instantly. Thanks for helping out! ❤️

[typescript-bot]

@GrapeGreen Thank you for reviewing this PR! The author has pushed new commits since your last review. Could you take another look and submit a fresh review?

[paulinagacek]

Ready to merge