feat: attachments fromAction utility

[paoloricciuti]

This provides a way to convert from action to attachments...this is useful if you are using a library that provides actions (like melt) and you want to spread them in dumb components.

<script>
	import Button from "./Button.svelte";
	import { log } from "log-my-number";
	import { fromAction } from "svelte/attachments";
	let count = $state(0);
</script>
<Button
	onclick={() => count++}
	{@attach fromAction(log, () => count)}
>
	{count}
</Button>

There's a slight type issue at the moment: if you have an optional argument to the action you will need to pass the second argument... I was not able to fix this yet but since I'm not sure if this will actually be merged I decided to put it out there to discuss and maybe someone better than me at TS will be able to fix it (or I'll fix it later since i have to go now)

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🦋 Changeset detected

Latest commit: 3672e29

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[svelte-docs-bot]

Preview: https://svelte-dev-git-preview-svelte-15933-svelte.vercel.app/

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Playground

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