Re-add partial hotword indicator exemption

The hotword indicator exemption was totally removed, instead of
conditionally removed on UDC. Correct the implementation so devices
without the hds_required sysprop set do not display the indicator when
hds/trusted is not used.

If HDS is not required, treat non-HDS VIService clients as trusted from the
ST perspective. Then fire an RECORD_AUDIO_HOTWORD op when detection
occurs (non-HDS clients only). This op is conditionally reported to the
user if HDS is required.

Addtl notes
 - Plumb args to do permission checks in the detector callback
 - Handle lack of perms identical to ST stack (return a pause)
 - Add logging for the requirement

This does not change any HDS behavior.

Fixes: 291869628
Test: CtsVoiceInteractionTestCases
Test: Indicator behavior on 2nd stage fail w + w/o requirement set for non-HDS
Change-Id: I7be92224bccf6f715ca492a2ffb124b242001cf1