build(deps-dev): bump express from 5.1.0 to 5.2.1

Bumps [express](https://github.com/expressjs/express) from 5.1.0 to 5.2.1.
- [Release notes](https://github.com/expressjs/express/releases)
- [Changelog](https://github.com/expressjs/express/blob/master/History.md)
- [Commits](expressjs/express@v5.1.0...v5.2.1)

---
updated-dependencies:
- dependency-name: express
  dependency-version: 5.2.1
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]

package-lock.json

@@ -14,7 +14,7 @@
     "axios": "^1.13.2",
     "browser-sync": "^3.0.4",
     "concurrently": "^9.2.1",
-    "express": "^5.1.0",
+    "express": "^5.2.1",
     "fast-glob": "^3.3.3",
     "github-markdown-css": "^5.8.1",
     "handlebars": "^4.7.8",