Allow binding to properties that are stores

[derolf]

Describe the problem

Allow binding to properties that are stores themselves.

Describe the proposed solution

<script>
	import { writable } from "svelte/store"
	
	const stores = {
            name: writable("foo")
        }
</script>

<input bind:value={$(stores.name)}/>

<h1>Hello {$(stores.name)}!</h1>

Alternatives considered

Destructuring, but that will not work with deeper nested structures.

Importance

would make my life easier

[Conduitry]

Essentially a duplicate of #4079.