Introduce a new production desktop shell at `shells/desktop/shell` built with C++20, Qt Quick/QML, and LayerShellQt, including top bar, launcher, desktop surfaces, shell state, and mock app data. Add the shared `packages/nebula-ui` QML module (theme, controls, focus, icons) and wire it into the shell build. Retire the old GTK/WebKit native host by removing `shells/desktop/native`, move the React shell UI to `shells/desktop/prototype-react` as an archived design reference, and update root/compositor/session documentation to reflect the new Linux-only production architecture and temporary Sway role.
Compositor
Sway is the temporary Wayland compositor while Nebula Desktop is developed. Configuration lives in sway/nebula-sway.conf.
Sway currently provides:
- Wayland compositor
- application window management
- XWayland
- input
- output handling
Nebula provides the visible shell (Qt Quick/QML via LayerShellQt). The Sway config must not enable a Sway bar.
A custom Nebula compositor is a later milestone. Do not treat this Sway setup as the final architecture.
Ubuntu/Linux
↓
Wayland
↓
Sway now
Nebula compositor later
↓
Nebula Shell
Qt Quick/QML