feat: add tray layout controls

internal/platform/platform_other.go

@@ -4,9 +4,13 @@ package platform
 
 import (
 	"errors"
+
 	"github.com/stevec/fancywin/internal/config"
 )
 
+func PrepareBackground()    {}
+func ShowError(_, _ string) {}
+
 func Run(_ string, _ config.Config, _ bool) error {
 	return errors.New("the window manager can only run on Windows")
 }