Closes #15037

This is a bit of weird one...the point is that the snippet was technically not accessing anything from the instance so it was hoisted but it was using bind:group so it needed the binding_group...i tried to think it it make sense to export a snippet with a bind group but i don't think it does (especially since we specify in the docs that for bind:group to work inputs needs to be in the same component) and i don't even think we could do it because even if we would accept the binding_group as an argument for the snippet a component that renders that snippet should know that it needs a binding_group in some way and i don't think it's doable.

However while trying to come up with various situations where the snippet could've been exported i noticed that we can technically "kinda" export snippets by passing them as prop. So a user could do something like this

App.svelte

<script>
    import Component from "./Component.svelte";
</script>

{#snippet radio(group, value)}
    <input type="radio", bind:group={group.selected} {value} />
{/snippet}

<Component {radio} />
<Component {radio} />

Component.svelte

<script>
    let { radio } = $props();
    let group = $state({ selected: undefined });
</script>

{@render radio(group, "A")}
{@render radio(group, "B")}

this is a bit weird because now App has the binding_group array but the state is inside Component. So i was wondering...should we disallow bind:group in snippets all togheter? Technically we can't do it now since it would be a breaking change but i wonder if we should do something about this weirdness.

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