Introduces a dedicated layer-shell `WindowChromeSurface` that renders macOS-style traffic-light controls over the focused Sway window titlebar, replacing the old top-bar window controls. Adds theme tokens and a reusable `TrafficLightButton` component, updates shell QML/CMake wiring, and adjusts Sway titlebar padding/title format so window titles do not overlap the overlay. Window tracking was extended with focused-window geometry/deco/fullscreen properties plus backend refresh support so the chrome follows window movement and state changes in near real time.
Introduces a new `WindowControls` component in the desktop top bar with minimize, maximize/restore, and close actions for the focused window. `WindowService` now exposes focused-window presence/maximized state plus focused-window convenience actions to support this UI.
Also extends Nebula UI with a reusable `NebulaToolTip`, keyboard/pressed-state support in `NebulaIconButton`, new window-control glyphs in `NebulaIcon`, and theme tokens for pressed/danger hover states, with CMake and README updates to register/document the new components.
andrew