Bump astro from 5.7.12 to 5.12.9 (#117)

Bumps [astro](https://github.com/withastro/astro/tree/HEAD/packages/astro) from 5.7.12 to 5.12.9.
- [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@5.12.9/packages/astro)

---
updated-dependencies:
- dependency-name: astro
  dependency-version: 5.12.9
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]

bun.lock

@@ -33,7 +33,7 @@
   },
   "devDependencies": {
     "@types/node": "22.15.17",
-    "astro": "5.7.12",
+    "astro": "5.12.9",
     "tsdown": "0.11.1",
     "typescript": "5.8.3"
   },

packages/astro-tunnel/package.json

@@ -11,7 +11,7 @@
     "astro": "astro"
   },
   "dependencies": {
-    "astro": "^5.7.12",
+    "astro": "^5.12.9",
     "astro-tunnel": "workspace:*",
     "@astrojs/check": "^0.9.4",
     "typescript": "^5.4.5"