Touching the graph trigering the FlPointerHoverEvent event in mobile devices

```dart
LineChart(
LineChartData(
lineTouchData: LineTouchData(
touchCallback: (FlTouchEvent event, LineTouchResponse? touchResponse) {
print("$event");
},
```

The first event fired after touching the mobile screen

```bash
I/flutter ( 7375): Instance of 'FlPointerHoverEvent'
```

The report identifies a LineChart with LineTouchData and a touchCallback, but names no repository file or test. Start by reproducing the snippet on a mobile device and tracing the touch-event dispatch; done means the initial mobile touch produces the expected event type without breaking other touch callbacks.

Written by the indexing model from the issue text.