Fix ScaleEvent: track prevScale and only send when scale actually changes

cmd/pad/main.go

@@ -40,6 +40,8 @@ func run(w *app.Window) error {
 
 	// Track pixel dimensions from ConfigEvent (for resize handling)
 	var pixelW, pixelH int
+	// Track previous scale to detect changes
+	prevScale := float32(1.0)
 
 	// Create logic instance with initial DP size and scale=1.0
 	logic := editor.NewLogic(initialDPW, initialDPH)
@@ -76,8 +78,9 @@ func run(w *app.Window) error {
 			newScale := gtx.Metric.PxPerDp
 
 			// If scale changed, send scale event to logic goroutine
-			if newScale != 1.0 {
+			if newScale != prevScale {
 				logic.ScaleChan() <- editor.ScaleEvent{Scale: newScale}
+				prevScale = newScale
 			}
 
 			// Convert pixel dimensions to DP using actual scale