- Use nixos-render-docs commonmark as the rendering engine
- Add GitHub source links (Declared by) for each option
- Fix installation.md links pointing to /docs/nix-module -> /docs/nix-options
- Replace 'Extra options' with greetd and getty autologin examples
- Add bash/zsh and fish variants for getty autologin
- Add link to Nix Module Options reference
- Clarify addLoginEntry only has effect when a DM is configured