feat: migrate to $app/state

[manuel3108]

Companion for #354 and sveltejs/kit#13140 respectively

• uses $app/state in the paraglide addon
• uses $app/state in the demo template

[changeset-bot]

🦋 Changeset detected

Latest commit: b9ad741

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]

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npm i https://pkg.pr.new/sveltejs/cli/sv@358

npm i https://pkg.pr.new/sveltejs/cli/svelte-migrate@358

commit: b9ad741

[eltigerchino]

Is it worth updating these test files too?

1. https://github.com/sveltejs/cli/blob/main/packages/core/tests/js/common/jsdoc-comment/input.ts
2. https://github.com/sveltejs/cli/blob/main/packages/core/tests/js/common/jsdoc-comment/output.ts

[Rich-Harris]

preview: https://svelte-dev-git-preview-cli-358-svelte.vercel.app/

this is an automated message

[manuel3108]

Is it worth updating these test files too?

Good catch, why not. Done.