fix(deps): update dependency astro to v6 [security]

Author: renovate[bot]

package.json

@@ -21,7 +21,7 @@
 		"@astrojs/rss": "4.0.15",
 		"@astrojs/sitemap": "3.7.0",
 		"@tailwindcss/vite": "4.1.18",
-		"astro": "5.18.1",
+		"astro": "6.1.6",
 		"astro-expressive-code": "^0.41.6",
 		"astro-icon": "^1.1.5",
 		"astro-robots-txt": "^1.0.0",