Change GestureDetector onPanDown to Listener onPointerDown

[asjqkkkk]

Description

to solve #425

before

        return GestureDetector(
          onPanDown: (_) => _stopScroll(canceled: true),
          excludeFromSemantics: true,

now

        return Listener(
          onPointerDown: (_) => _stopScroll(canceled: true),

onPanDown of GestureDetector will get a conflict with some widgets, such as SelectionArea
use Listener can solve this issue

Related Issues

#425

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