Bump svelte from 5.53.6 to 5.55.8 in /src/ifctester/webapp

Bumps [svelte](https://github.com/sveltejs/svelte/tree/HEAD/packages/svelte) from 5.53.6 to 5.55.8.
- [Release notes](https://github.com/sveltejs/svelte/releases)
- [Changelog](https://github.com/sveltejs/svelte/blob/main/packages/svelte/CHANGELOG.md)
- [Commits](https://github.com/sveltejs/svelte/commits/svelte@5.55.8/packages/svelte)

---
updated-dependencies:
- dependency-name: svelte
  dependency-version: 5.55.8
  dependency-type: direct:development
...

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