The hyprcorrect GUI: the egui preferences window and (later, M4) the keyboard-navigable suggestion popup.
All UI in this crate is platform-independent egui — Linux and
macOS share the same code. The run_preferences entry handles a
best-effort singleton lock so double-clicking "Open Preferences…"
in the tray doesn't open two windows.
See the "Configuration & GUI" section of DESIGN.md.