fix: improve namespace inference when having {@render} and {@html} tags

[navorite]

When using {@render ...} in a component that has only svg nodes, the namespace gets the maybe_html value which returns the default namespace (html). Instead {@render ...} should be treated like child components, they should not affect the component's namespace.

I also simplified the code a bit.

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[dummdidumm]

The simplification is great, thank you!
I'm not sure yet if we should change the behavior. Do you have a concrete use case where this yielded wrong results?
If we changed this, shouldn't we also change it for {@html ..}?

[navorite]

The simplification is great, thank you! I'm not sure yet if we should change the behavior. Do you have a concrete use case where this yielded wrong results? If we changed this, shouldn't we also change it for {@html ..}?

REPL

I think we should do the same for {@html ..} since this is what happens in Svelte 4 and it also makes more sense. I'll make that change as well.

[Rich-Harris]

thank you!