Implement StylusListener SystemUI CoreStartable.

StylusListener detects first usage of a stylus, and
updates the STYLUS_EVER_USED Settings flag.

Bug: 251206662
DD: go/stylus-first-usage-options
Test: StylusListenerTest
Change-Id: I165481d1166e31b5b8560da5c695003d105068ef
6 files changed