Bump fumadocs-mdx from 12.0.3 to 13.0.2 in /docs

Bumps [fumadocs-mdx](https://github.com/fuma-nama/fumadocs) from 12.0.3 to 13.0.2.
- [Release notes](https://github.com/fuma-nama/fumadocs/releases)
- [Commits](https://github.com/fuma-nama/fumadocs/compare/fumadocs-mdx@12.0.3...fumadocs-mdx@13.0.2)

---
updated-dependencies:
- dependency-name: fumadocs-mdx
  dependency-version: 13.0.2
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]