build(deps): bump the default group across 1 directory with 4 updates

Bumps the default group with 3 updates in the / directory: [markdown-it](https://github.com/markdown-it/markdown-it), [@types/node](https://github.com/DefinitelyTyped/DefinitelyTyped/tree/HEAD/types/node) and [@vitest/coverage-v8](https://github.com/vitest-dev/vitest/tree/HEAD/packages/coverage-v8).


Updates `markdown-it` from 14.1.0 to 14.1.1
- [Changelog](https://github.com/markdown-it/markdown-it/blob/master/CHANGELOG.md)
- [Commits](markdown-it/markdown-it@14.1.0...14.1.1)

Updates `@types/node` from 25.0.3 to 25.2.3
- [Release notes](https://github.com/DefinitelyTyped/DefinitelyTyped/releases)
- [Commits](https://github.com/DefinitelyTyped/DefinitelyTyped/commits/HEAD/types/node)

Updates `@vitest/coverage-v8` from 4.0.16 to 4.0.18
- [Release notes](https://github.com/vitest-dev/vitest/releases)
- [Commits](https://github.com/vitest-dev/vitest/commits/v4.0.18/packages/coverage-v8)

Updates `vitest` from 4.0.16 to 4.0.18
- [Release notes](https://github.com/vitest-dev/vitest/releases)
- [Commits](https://github.com/vitest-dev/vitest/commits/v4.0.18/packages/vitest)

---
updated-dependencies:
- dependency-name: markdown-it
  dependency-version: 14.1.1
  dependency-type: direct:production
  update-type: version-update:semver-patch
  dependency-group: default
- dependency-name: "@types/node"
  dependency-version: 25.2.3
  dependency-type: direct:development
  update-type: version-update:semver-minor
  dependency-group: default
- dependency-name: "@vitest/coverage-v8"
  dependency-version: 4.0.18
  dependency-type: direct:development
  update-type: version-update:semver-patch
  dependency-group: default
- dependency-name: vitest
  dependency-version: 4.0.18
  dependency-type: direct:development
  update-type: version-update:semver-patch
  dependency-group: default
...

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

Author: dependabot[bot]