docs: more build docs

[dummdidumm]

Transforming the adapters document into a more general build doc Closes #8436

The alternative to this is to introduce another top level document (keeping the adapter doc as is) - I'm fine with that, too. Maybe I actually prefer that; opened #8501 for comparison

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🦋 Changeset detected

Latest commit: b5889181fbdf11805bb5243ad42e6e23d893623a

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

This PR includes changesets to release 6 packages

Name	Type
@sveltejs/adapter-auto	Patch
@sveltejs/adapter-cloudflare	Patch
@sveltejs/adapter-node	Patch
@sveltejs/adapter-static	Patch
create-svelte	Patch
@sveltejs/kit	Patch

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[benmccann]

I really hate that we have to bump the adapter packages everytime we update their docs. Maybe we should take this opportunity to move their docs from the READMEs to the docs folder?

That gives me another idea which would be to create a Building Your App section. Within that could live the new page, the general adapters docs, and docs for each individual official adapter.

[Rich-Harris]

closing in favour of #8531