feat: add renderStaticHTML to render a component without hydration markers

[paoloricciuti]

Closes #14337

we talked about this this afternoon with @trueadm ...for the moment this is just the implementation of rendering without hydration markers. I'll get to the "awaiting the the awaits" probably tomorrow (we also discussed about the possible implementation of that).

Just putting this up so it should be easier to focus on the await part later on.

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[Rich-Harris]

preview: https://svelte-dev-git-preview-svelte-14353-svelte.vercel.app/

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[github-actions]

Playground

pnpm add https://pkg.pr.new/svelte@14353

[Rich-Harris]

I don't think we should do this. The comments are harmless unless you're doing something really niche, in which case this is easily solved in userland.

[paoloricciuti]

I don't think we should do this. The comments are harmless unless you're doing something really niche, in which case this is easily solved in userland.

Yeah we were talking about that with @trueadm just now...it's fine. I was almost done implementing the await of await blocks so i'll finish that up just for funzies and just so that we might have a reference implementation when and if we add something similar

[trueadm]

I'm going to close this, as to not give people a false idea on new APIs coming. However, we should definitely keep it around as a future reference starting point.