Update for Node.js LTS v18 Compatibility and Dependency Fixes

[laiso]

Thank you for sharing your excellent software. @jzillmann Based on 'Release 0.1.3', I have made modifications to run the application in my current Node.js LTS (v18) environment. I believe these changes could be beneficial to other users, so I am submitting this as a pull request. I've updated npm dependencies and resolved errors occurring during npm build. Please note that my changes might not maintain compatibility with certain aspects like type checking

❯ npm i
❯ npm run build
❯ npm start

> pdf-to-markdown@0.1.3 start
> webpack serve

ℹ ｢wds｣: Project is running at http://localhost:8080/
ℹ ｢wds｣: webpack output is served from /

[jzillmann]

Thanks @laiso looks good!