[1/n] Create Configuration for CompatUX Enhancements

This flags allow to enable/disable some of the new compat ui
enhancements related to a confirmation dialog for restart button
and an education for letterbox reachability.

Fixes: 260909953
Test: Manual using `adb shell dumpsys activity service SystemUIService
WMShell compatui <command> <value>` where commands are `restartDialogEnabled`
and `reachabilityEducationEnabled` and the values `0, false, 1 or true`

Change-Id: I10a99cc73d97026e12d4c60b751d349281b1d1cf