Update app.py

app.py

@@ -3602,7 +3602,7 @@ SPRITE_DIR   / "Abby.sprite3" / "34a175600dc009a521eb46fdbbbeeb67.png"
                     "assetId": default_backdrop_name.split(".")[0],
                     "name": "defaultBackdrop",
                     "md5ext": default_backdrop_name,
-                    "dataFormat": "png",
+                    "dataFormat": "svg",
                     "rotationCenterX": 240,
                     "rotationCenterY": 180
                 }