Add tag attribute for VisualQueryDetectionService

The tag attribute is added to distinguish the
VisualQueryDetectionService that VoiceInteractor is using to build
service conncetion to. This is a prestep necessary of developing and
test the upcoming CLs regarding the implementation of VQDS.

Bug: 261783491
Test: Manual
Change-Id: I04855911256aa458be45707b49f369dc54c506de