build(deps-dev): bump @babel/preset-env from 7.28.5 to 7.29.2 in /demo

Bumps [@babel/preset-env](https://github.com/babel/babel/tree/HEAD/packages/babel-preset-env) from 7.28.5 to 7.29.2.
- [Release notes](https://github.com/babel/babel/releases)
- [Changelog](https://github.com/babel/babel/blob/main/CHANGELOG.md)
- [Commits](https://github.com/babel/babel/commits/v7.29.2/packages/babel-preset-env)

---
updated-dependencies:
- dependency-name: "@babel/preset-env"
  dependency-version: 7.29.2
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

demo/package.json

@@ -35,7 +35,7 @@
     "markdown-it": "catalog:peers"
   },
   "devDependencies": {
-    "@babel/preset-env": "7.28.5",
+    "@babel/preset-env": "7.29.2",
     "@babel/preset-react": "7.28.5",
     "@babel/preset-typescript": "7.28.5",
     "@bem-react/classname": "^1.6.0",