AmbientLightModeInteractor Introduction

This changelist introduces AmbientLightMonitorInteractor, which allows
for the current AmbientLightMonitor to be updated. This is useful for
applications where different AmbientLightMonitors might be used under
various conditions, such as lighting.

This change also makes the brightness sensors previously restricted to
Doze available to the rest of SystemUI.

Test: atest LowLightBehaviorCoreStartableTest
Bug: 432103856
Flag: EXEMPT bugfix
Change-Id: I07b4c77a19aed79f4c1f29720f41491eaeb11d4a