Bump astro from 5.17.3 to 5.18.0 in the astro-and-starlight group (#343)

Bumps the astro-and-starlight group with 1 update: [astro](https://github.com/withastro/astro/tree/HEAD/packages/astro).


Updates `astro` from 5.17.3 to 5.18.0
- [Release notes](https://github.com/withastro/astro/releases)
- [Changelog](https://github.com/withastro/astro/blob/astro@5.18.0/packages/astro/CHANGELOG.md)
- [Commits](https://github.com/withastro/astro/commits/astro@5.18.0/packages/astro)

---
updated-dependencies:
- dependency-name: astro
  dependency-version: 5.18.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
  dependency-group: astro-and-starlight
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

package-lock.json

@@ -23,7 +23,7 @@
     "@astrojs/sitemap": "^3.7.0",
     "@astrojs/starlight": "^0.37.6",
     "@zachleat/snow-fall": "^1.0.3",
-    "astro": "^5.17.3",
+    "astro": "^5.18.0",
     "astro-compress": "^2.3.9",
     "astro-og-canvas": "^0.10.1",
     "sharp": "^0.34.5",