Default by spliting addons in 2 parts

[jycouet]

Description

Today the add-on is bundled in 1 file, that makes it hard to know what is it doing.
With this new default setup we have 2 files... index & sv-utils.

Checklist

• Update snapshots (if applicable)
• Add a changeset (if applicable)
• Allow maintainers to edit this PR
• I care about what I'm doing, no matter the tool I use (Notepad, Sublime, VSCode, AI...)

[changeset-bot]

⚠️ No Changeset found

Latest commit: f2acbf9

Merging this PR will not cause a version bump for any packages. If these changes should not result in a new version, you're good to go. If these changes should result in a version bump, you need to add a changeset.

This PR includes no changesets

When changesets are added to this PR, you'll see the packages that this PR includes changesets for and the associated semver types

Click here to learn what changesets are, and how to add one.

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[pkg-pr-new]

Open in StackBlitz

npx https://pkg.pr.new/svelte-migrate@1032

npx https://pkg.pr.new/sv@1032

npx https://pkg.pr.new/@sveltejs/sv-utils@1032

commit: f2acbf9

[svelte-docs-bot]

Preview: https://svelte-dev-git-preview-cli-1032-svelte.vercel.app/