chore: improve cli help menu

[manuel3108]

Closes #195

Depends on https://github.com/tj/commander.js/pull/2251, we should only merge this PR, once commander has been update. This PR is used to generate a preview package, so people can try this out.

Edit: Package cannot be a devDependency right now, as rollup is presumably breaking it while transpiling.

[changeset-bot[bot]]

🦋 Changeset detected

Latest commit: 783f7a20e2712efc96acf1c3fe3ee1338fef0dc3

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

This PR includes changesets to release 1 package

| Name | Type | | ---- | ----- | | sv | Patch |

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[pkg-pr-new[bot]]

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pnpm add https://pkg.pr.new/sveltejs/cli/sv@294

pnpm add https://pkg.pr.new/sveltejs/cli/svelte-migrate@294

commit: 783f7a2