fix: place store setup inside async body

[Ocean-OS]

Closes #16682

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[changeset-bot]

🦋 Changeset detected

Latest commit: 9d6e854

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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[github-actions]

Playground

pnpm add https://pkg.pr.new/svelte@16687

[sillvva]

There's a bug: https://svelte.dev/playground/25e885f15619494084ca088695e7d004?version=pr-16687

import 'svelte/internal/disclose-version';
import 'svelte/internal/flags/async';
import * as $ from 'svelte/internal/client';
import { writable } from "svelte/store";

export default function App($$anchor, $$props) {
	$.push($$props, true);

	$.async_body(async () => {
		const [$$stores, $$cleanup] = $.setup_stores();
		const $w = () => $.store_get(w, '$w', $$stores);
		let w = writable("store");

		(await $.save(Promise.resolve("test")))();

		if ($.aborted()) return;

		$.next();

		var text = $.text();

		$.template_effect(() => $.set_text(text, $w()));
		$.append($$anchor, text);
	});

	$.pop();
	$$cleanup(); // this is defined inside the async_body scope
}

[Ocean-OS]

Found another bug, working on a fix.