feat: hidden until found and beforematch

[fcrozatier]

The until-found value of the hidden attributes allows find-in-page functionnality, and the beforematch event can intercept it.

spec MDN REPL

Svelte 5 rewrite

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[changeset-bot]

🦋 Changeset detected

Latest commit: 097c934

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

This PR includes changesets to release 1 package

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svelte	Patch

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[trueadm]

Thank you :)