fix: possible name clash in hoisted functions

[paoloricciuti]

Svelte 5 rewrite

This come up on Discord here. Basically if you are accessing a store with the auto-subscription AND normal store object in a hoisted function it will generate the parameters with double the occurences of store leading to a Syntax error.

See the problematic code

<script lang="ts">
	import { writable } from 'svelte/store';
	const store = writable(0);
	
	async function logStore() {
		console.log($store)
		store.set(100);
	}
</script>

<button onclick={logStore}>Click me</button>

This fixes this by safe pushing an identifier in the parameter array only if it's not already present.

I've also added a test that is failing before the fix...i was not super sure how to properly do it so i just left the config basically void without asserting anything but it was failing before and it is not failing now.

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[changeset-bot]

🦋 Changeset detected

Latest commit: 812d7fb

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

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[dummdidumm]

Thank you!