docs: address spec review — complete interfaces, fix insulation gaps
Fixes from code review:
- Window type is own struct, not Wails alias; WindowOption rewrites
- PlatformWindow interface: add Position, Size, IsMaximised, IsFocused,
Show, Hide, Fullscreen, UnFullscreen, OnWindowEvent
- Package-level vars (activeTray, trayMenuCallbacks) become Manager fields
- Menu click handlers live in pkg/display, pkg/menu builds structure only
- WSEventManager insulation via EventSource + PlatformWindow interfaces
- WindowStateManager accepts PlatformWindow, returns own Window struct
- AttachWindow uses display.WindowHandle, not any
- ui/ existing Angular code moves as-is, go:embed updates
Co-Authored-By: Virgil <virgil@lethean.io>
99a8dda8d2