fix: ensure $inspect works with SvelteMap and SvelteSet

[trueadm]

Turns out that we broke $inspect at some point and it stopped working with SvelteMap and SvelteSet. This fixes that.

[changeset-bot]

🦋 Changeset detected

Latest commit: 85a73b6

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

This PR includes changesets to release 1 package

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svelte	Patch

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[Conduitry]

I realize it's just a handful of bytes, but are there other common use cases besides $inspect() where someone would want to have a toJSON() on these objects? If not, adding this for the sake of a dev-time-only feature bugs me.

[trueadm]

I realize it's just a handful of bytes, but are there other common use cases besides $inspect() where someone would want to have a toJSON() on these objects? If not, adding this for the sake of a dev-time-only feature bugs me.

It's an odd one too. structuredClone seems to bypass all the other methods internally. I can make this DEV only though.

[Rich-Harris]

With this PR, the behaviour of this code will differ between dev and prod:

$effect(() => {
  console.log('map snapshot', $state.snapshot(map));
});

We can't have that. I think we should just trigger the relevant reactivity inside clone.js by adding something like this:

if (value instanceof Map) new Map(value);
if (value instanceof Set) new Set(value);