To make #57871 easier to land, add support for loading either LICENSES or NOTICES, preferring the later.

This adds a new navigationMode to the MediaQueryData that indicates how focusable controls should behave under different navigation modes, currently with two modes: NavigationMode.traditional, and NavigationMode.directional.

It may seem like focusing a disabled control is not desirable, but this is useful for user interfaces that use DPAD navigation because if a control gets disabled, losing focus is disruptive to the user, and it is difficult to control where the focus will end up unless it is done explicitly.

Add code example for CustomScrollView on how to make it grow in two directions along its scroll axis (#57670)

* Have _warpToCurrentIndex() shortcut logic behave properly

* Add test

* Apply code review

* Fix typo (fromm -> from)

* Value Indicator uses Global position when calculating horizontal position

* fixed test

* fixed analyzer

* Made globalCenter variable and added comments