Bump svelte from 3.59.1 to 4.2.1 in /pagefind_ui/default

Bumps [svelte](https://github.com/sveltejs/svelte/tree/HEAD/packages/svelte) from 3.59.1 to 4.2.1.
- [Release notes](https://github.com/sveltejs/svelte/releases)
- [Changelog](https://github.com/sveltejs/svelte/blob/master/packages/svelte/CHANGELOG.md)
- [Commits](https://github.com/sveltejs/svelte/commits/[email protected]/packages/svelte)

---
updated-dependencies:
- dependency-name: svelte
  dependency-type: direct:development
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <[email protected]>