chore: remove some todos

[Ocean-OS]

This removes some // TODO comments. It shouldn't change much behavior-wise, as it's mostly tweaks to types.
Since this does change an AST node's type, I will update #16188 once this is merged.

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🦋 Changeset detected

Latest commit: 59ac067

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

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[svelte-docs-bot]

Preview: https://svelte-dev-git-preview-svelte-16515-svelte.vercel.app/

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Playground

pnpm add https://pkg.pr.new/svelte@16515

[7nik]

Evaluation of SpreadElement will result in UNKNOWN anyway, so the first check can be removed, right?
And maybe it's cleaner to add has/is_unknown prop-flag to Evaluation and use it here.

[Ocean-OS]

Scope.evaluate's parameters only accept an Expression node, which does not include SpreadElements.
I'll add the has unknown check in a bit.

[Rich-Harris]

I actually don't think we can rename Comment without it being a breaking change (for e.g. svelte-ast-print or anything else that operates on the AST). Even though we've stated that it's subject to change, I don't think we should change things like this unless we really need to. It's already disambiguated enough in my view — AST.Comment vs e.g. ESTree.Comment

[Ocean-OS]

If you were to walk a Svelte AST, you wouldn't easily know the difference between an ESTree comment and a Svelte comment. Stuff like printing would get a bit ugly as you'd have to check the type of the parent node against a large group of possible types.
I do agree that there is the concern of this being a breaking change, but to be honest are there really that many things dependent on the Svelte AST types? Not to mention that svelte-ast-print will likely be sunsetted when the print function is merged.