Initial implementation of system service optimizations for different type of users.

On R, we want to optimize boot time by not starting system services for some types of users,
like a headless system user (which is the case for Automotive)

As a "guinea pig", it optimizes VoiceInteractionService for headless system user, so the 3rd-party app
service is not bound for user 0 (and hence its process is not launched).

This change improves boot time on Automotive in about 100ms.

Test: atest CtsVoiceInteractionTestCases CtsAssistTestCases # on walleye and Automotive
Test: manual verification on logcat

Bug: 133242016
Fixes: 137878080

Change-Id: Ib0a902855e32691a1d00bfa77ee82c8e2430977c