feat: add GamepadEventHandler type

[ntsd]

Add GamepadEventHandler type for window.addEventListener gamepadconnected and gamepaddisconnected

Ref: https://developer.mozilla.org/en-US/docs/Web/API/GamepadEvent

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• It's really useful if your PR references an issue where it is discussed ahead of time. In many cases, features are absent for a reason. For large changes, please create an RFC: https://github.com/sveltejs/rfcs
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• This message body should clearly illustrate what problems it solves.
• Ideally, include a test that fails without this PR but passes with it.

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[changeset-bot]

🦋 Changeset detected

Latest commit: b049d64

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
svelte	Patch

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[dummdidumm]

Thank you! Do you need this in Svelte 4 as well? Because this PR targets the Svelte 5 branch.

[ntsd]

Thank you! Do you need this in Svelte 4 as well? Because this PR targets the Svelte 5 branch.

Yes, but not sure where to add. Oh thank you I just saw svelte-4

[dummdidumm]

The Svelte 4 branch is svelte-4. You need to make the commit against that (but keep this one open, we need one PR for each branch).
Also, please add a changeset using npx changeset

[ntsd]

The Svelte 4 branch is svelte-4. You need to make the commit against that (but keep this one open, we need one PR for each branch). Also, please add a changeset using npx changeset

Done, ready for review.

[dummdidumm]

Thank you! Remember to create the same PR (minus the ongame... variants) again the svelte-4 branch.

[ntsd]

Thank you! Remember to create the same PR (minus the ongame... variants) again the svelte-4 branch.

Thank you, Link to the Svelte 4 PR #9864.