chore(deps): bump astro and @astrojs/svelte

Bumps [astro](https://github.com/withastro/astro/tree/HEAD/packages/astro) and [@astrojs/svelte](https://github.com/withastro/astro/tree/HEAD/packages/integrations/svelte). These dependencies needed to be updated together.

Updates `astro` from 5.17.1 to 6.1.8
- [Release notes](https://github.com/withastro/astro/releases)
- [Changelog](https://github.com/withastro/astro/blob/main/packages/astro/CHANGELOG.md)
- [Commits](https://github.com/withastro/astro/commits/astro@6.1.8/packages/astro)

Updates `@astrojs/svelte` from 7.2.5 to 8.0.5
- [Release notes](https://github.com/withastro/astro/releases)
- [Changelog](https://github.com/withastro/astro/blob/main/packages/integrations/svelte/CHANGELOG.md)
- [Commits](https://github.com/withastro/astro/commits/@astrojs/svelte@8.0.5/packages/integrations/svelte)

---
updated-dependencies:
- dependency-name: astro
  dependency-version: 6.1.8
  dependency-type: direct:production
- dependency-name: "@astrojs/svelte"
  dependency-version: 8.0.5
  dependency-type: direct:production
...

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