Filter trigger for desktop windowing education

A trigger is an event, like user interaction or system event that can serve as an entry point to initiate user education.
After a trigger occurs, that trigger is filtered based on various conditions.
Filtering is controlled by the WindowingEducationFilter class. WindowingEducationFilter#shouldShowEducation() is the public api used to get the result of filtering.

Bug: 353744739
Bug: 353987858
Test: AppHandleFilterTest
Flag: com.android.window.flags.enable_desktop_windowing_app_handle_education
Change-Id: I795472bb299b8880876f7c72ac077729d4208d62