chore: add Node.js version requirement (>=22.0.0)

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Co-Authored-By: Claude <noreply@anthropic.com>

Author: ericyangpan

package.json

@@ -86,6 +86,9 @@
     "url": "https://github.com/aicodingstack/aicodingstack.io/issues"
   },
   "homepage": "https://github.com/aicodingstack/aicodingstack.io#readme",
+  "engines": {
+    "node": ">=22.0.0"
+  },
   "browserslist": [
     "defaults and fully supports es6-module",
     "maintained node versions"