fix: properly add owners to function bindings

[paoloricciuti]

Closes #14956

The ownership stuff was specifically guarded against the SequenceExpression so i'm not sure if this is has any downside but for the moment let's open the PR so we can eventually discuss. I've added the owner to every stateful identifier in the get function only since that's the only part the child component could mutate in some way (i wonder if we should actually just consider the identifiers returned from the function instead of every identifier).

Also also i discovered that we were adding the same identifier multiple times in situations like this

<Component bind:arr={arr} bind:arr2={arr} />

there were two add_owner_effect's added which is wasteful. I did that fix in a separate commit so if we decide against this change we can always merge revert it and merge the fix for multiple effects separately.

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pnpm add https://pkg.pr.new/svelte@14960

[Rich-Harris]

I'm not sure this works? If the identifiers referenced inside the getter aren't themselves state...

<script>
	// ...

	function getter() {
		return len % 2 === 0 ? arr : arr2
	}
</script>

<Child bind:arr={getter, (v) => {}} />

...then the warning still occurs. Surely we just need to call the getter? Opened #14962

[paoloricciuti]

Surely we just need to call the getter?

Oh yeah that's better...even tho it's an extra call to the getter technically people shouldn't do side effects there...closing this.