- Replace mkdocs with docosaurus (improved menu structure, ...)
- Structure docs into `Usage` and `Server Setup / Administration`
- Update favicon
- Create new pipeline-syntax page with all options and links to more detailed docs if available
- Add ci to publish to `woodpecker-ci.github.io`
- Deploy docs preview to surge for review
- Update start-page
Co-authored-by: 6543 <6543@obermui.de>