Add flows for whether user is interacting with the shade

These flows will serve as a replacement for the concept of "tracking"
used throughout NPVC and QSC. "Tracking" means that the user is
touching with the screen and moving the shade or quick settings.
The change will modify the concept to make it continue to be true
after the user has lifted their finger but any transitions they
triggered are still animating. Previously, many things had to
cache the value of tracking in order to remember the value after
the user had lifted their finger, so this change will remove the
need for that. Flexiglass impls of the new flows will be added
behind flags in the next CL.

Bug: 300254715
Test: updated and ran affected tests
Test: manually checked shade CUJs
Change-Id: I9dc4e1a6d6f4ad6e1003ecb2d1a9beb2096e9b9f