chore: unify svelte-migrate to sv

[manuel3108]

Initial goal here was to unify the UX between stuff like sv create and svelte-migrate

done:

• use picocolors instead of kleur
• use @clack/prompts instead of prompts

todo:

• print package version and intro similar to sv
• print outro (also if action is cancelled or process is exited)
• remove most console.log as they look ugly inside the prompts and convert them to notes or information etc.
• unify code (there is so much trivially duplicated code)
• closes List out options for npx sv migrate #302

I opted to not use our own @sveltejs/clack-prompts package and instead use the public one. Using our own package would either require us to publish the package, or include svelte-migrate inside our own rollup config to bundle it. Not a fan of both options, thus decided to use the public package instead.

[changeset-bot]

🦋 Changeset detected

Latest commit: 12d5c5f

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

This PR includes changesets to release 1 package

Name	Type
svelte-migrate	Patch

Not sure what this means? Click here to learn what changesets are.

Click here if you're a maintainer who wants to add another changeset to this PR

[pkg-pr-new]

Open in Stackblitz

npm i https://pkg.pr.new/sveltejs/cli/sv@376

npm i https://pkg.pr.new/sveltejs/cli/svelte-migrate@376

commit: 651b3c2

[Rich-Harris]

preview: https://svelte-dev-git-preview-cli-376-svelte.vercel.app/

this is an automated message

[manuel3108]

There are obviously lots of potential improvements that could still be done here. The main goal here was to unify the UX and this is a huge step forward imo.

The following things might be done at a later stage:

• use package-manager-detector from {pm} install messages
• further deduplicate and unify source code
• deprecate old migrations / remove the respective source code and make the users use [email protected]