This PR is adding a flag parameter to the `TextField` widget. This flag controls whether the TextField ignores pointers. The flag takes priority over other TextField behaviors such as enabled, so it can be useful when trying to have a disabled TextField that can be scrolled (behavior observed using TextArea on the web).

Adding a flag parameter to `TextField` helps with more customization and flexibility to the widget which can improve user experience. I am open to other ideas.   

Fixes issue #140147 

Before: 

https://github.com/flutter/flutter/assets/66151079/293e5b4e-3126-4a00-824d-1530aeaa494b

After:

https://github.com/flutter/flutter/assets/66151079/08c1af09-3bf9-4b49-b684-dda4dd920503

Usage:
```dart
child: TextField(
  ignorePointer: false,
  enabled: false,
),
```