Revert React 19 for docs site

Author: martijnrusschen

docs-site/package.json

@@ -4,8 +4,8 @@
   "private": true,
   "dependencies": {
     "highlight.js": "^11.11.1",
-    "react": "^19.0.0",
-    "react-dom": "^19.0.0",
+    "react": "^18.3.1",
+    "react-dom": "^18.3.1",
     "react-live": "^4.1.8"
   },
   "scripts": {