Modernize Docs

[SeferMirza]

Modernization of baked docs to use tailwind, improved dev mode and possibly some
usages of primevue where possible

Tasks

• remove prebuild submodule
• refactor config.yml and remove extract diagrams
• use prebuild to watch document changes
• add prebuild as a package
• use tailwind
  • use tailwind 4.1
  • migrate brand utility class usages to tailwind
  • use variables for font-size, spacing and colors
  • migrate custom classes in .scss
  • migrate page sizes to those in tailwind
  • migrate style tags in .vue files
  • test all components and pages in all screen sizes
  • reorder all classes alphabetically
• mermaid style adjustment

Additional Tasks

• brand update Remove Obsolete Styles brand#12
• fix "on this page" and "pages" title layout issue on mobile