fix: always set draggable through setAttribute to avoid weird behavior

[paoloricciuti]

Svelte 5 rewrite

Closes #12643

Very weird behaviour from the draggable setter...if you set element.draggable="false" it will actually set draggable to true (the boolean).

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Latest commit: d4d7c14

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

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[Serator]

Hi @paoloricciuti. https://github.com/sveltejs/svelte/pull/12649/files#diff-87ec8cbb1aa898b9a6bc0e9dde2e355df357844becd562b80386d0bf4713b57fR344-R345 - there are other HTMLElement properties. Here's a possibly incomplete list:

• autofocus
• draggable
• hidden
• inert
• isContentEditable (the related HTML attribute contenteditable has more values)
• spellcheck
• translate

Either way, new properties / attributes will be added over time.

Reproduction link