Update react monorepo to v19

Author: renovate[bot]

examples/react/package.json

@@ -10,8 +10,8 @@
     "babel-polyfill": "6.26.0",
     "concurrently": "9.2.1",
     "pouchdb-server": "4.2.0",
-    "react": "18.3.1",
-    "react-dom": "18.3.1",
+    "react": "19.2.6",
+    "react-dom": "19.2.6",
     "rxdb": "file:rxdb-local.tgz",
     "rxjs": "7.8.2"
   },