Fix #660: add cover art, silent property to Windows track change notification

backend/windows/notify_unsupported.go

@@ -0,0 +1,10 @@
+//go:build !windows
+
+package windows
+
+import "fyne.io/fyne/v2"
+
+func SendNotification(n *fyne.Notification, iconFilePath string) {
+	fyne.LogError("windows.SendNotification should not be invoked on non-Windows platform", nil)
+	fyne.CurrentApp().SendNotification(n)
+}