docs: add cli documentation link

[hyunbinseo]

I didn't know sv create had such comprehensive documentation.

Adding the package documentation link in the README will help.

[benmccann]

Could you also add a link to the docs from https://github.com/sveltejs/cli/blob/main/packages/cli/README.md?

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Latest commit: 35c6e81

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commit: 35c6e81