Update all npm dependencies (2025-07-19)

package.json

@@ -32,8 +32,8 @@
   },
   "dependencies": {
     "@astrojs/check": "^0.9.4",
-    "@astrojs/markdown-remark": "^6.3.2",
-    "@astrojs/mdx": "^4.3.0",
+    "@astrojs/markdown-remark": "^6.3.3",
+    "@astrojs/mdx": "^4.3.1",
     "@astrojs/react": "^4.3.0",
     "@astrojs/rss": "^4.0.12",
     "@astrojs/sitemap": "^3.4.1",
@@ -57,7 +57,7 @@
     "@types/react-dom": "19.1.6",
     "@vercel/routing-utils": "^5.1.1",
     "@vercel/speed-insights": "^1.2.0",
-    "astro": "^5.11.1",
+    "astro": "^5.12.0",
     "astro-expressive-code": "^0.41.3",
     "astro-icon": "^1.1.5",
     "class-variance-authority": "^0.7.1",