fix: update to flake.nix

documentation/manual/de/book/print.html

documentation/manual/de/book/searcher.js

documentation/manual/de/book/searchindex.js

documentation/manual/de/book/searchindex.json

documentation/manual/de/book/theme-dawn.js

documentation/manual/de/book/theme-tomorrow_night.js

documentation/manual/de/book/tomorrow-night.css

documentation/manual/de/mdbook-admonish.css

documentation/manual/de/mermaid-init.js

documentation/manual/de/mermaid.min.js

documentation/manual/de/source/01-Einleitung.md

documentation/manual/de/source/02-Erste-Schritte.md

documentation/manual/de/source/404.md

documentation/manual/de/source/SUMMARY.md

documentation/manual/de/source/imprint.md

documentation/manual/de/theme/book.js

error.go

flake.lock

flake.nix

go.mod