Share process between SandboxedDetectionServices

Bind HotwordDetectionService and SandboxedDetectionService in to a
single isolated process instance and share AppOps and policy between the
two services.

Bug: 255597123
Test: manual - sample app can open camera with few wip CLs
Change-Id: Ibb68532435cdd1fba724010b538ecf065c517b0c