fix: allow runelike writable as prop

[paoloricciuti]

Svelte 5 rewrite

Closes #11742

I had to guard against props being the store name because a situation like this doesn't make sense

<script>
    let { props } = $props();
</script>

{$props}

because disabling props as a rune in favor of a prop being a store would mean you cannot access the writable in the first place (kinda convoluted i know). Should we throw a more descriptive error in that case?

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[dummdidumm]

We could adjust the error message, but I think that case is so rare we don't need to worry about it

[paoloricciuti]

We could adjust the error message, but I think that case is so rare we don't need to worry about it

New Issue: confusing error when passing a store that is named props to component 😄 😄 😄