Improve: NOverlayImage.fromWidget delete Image Widget support.

Author: note11g

lib/src/type/map/overlay/overlay_image.dart

@@ -28,6 +28,9 @@ class NOverlayImage with NMessageableWithMap {
     required Size size,
     required BuildContext context,
   }) async {
+    assert(widget.runtimeType != Image,
+        "Do not use Image widget.\n"
+            "Instead, using `NOverlayImage.fromAssetImage` or `.fromFile` or `.fromByteArray` Constructor.");
     final imageBytes = await WidgetToImageUtil.widgetToImageByte(widget,
         size: size, context: context);
     final path = await ImageUtil.saveImage(imageBytes);