fix: use typedef for JSDoc props and maintain comments

[paoloricciuti]

Svelte 5 rewrite

Closes #13631

To "keep the comment" i cleaned up the jsdoc comment a bit removing the * and the /** and */. Since a lot of stuff in the jsdoc is just JSDoc instead of an actual comment i stop at the first comment that starts with @ but i don't know if this is the right strategy. Let's talk about it.

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