cameraservice: Copy camera characteristics from session characteristics

The getSessionCharacteristics call is meant to replace the output of
getCameraCharacteristics. The current implementation however passed
the output of HAL directly to the application, which could be missing
quite a few keys.

This CL uses the camera device's characteristics as the base
and copies over any updated values from the HAL instead. This will
ensure the output of getSessionCharacteristics matches the constraints
of getCameraCharacteristics.

Similarly, this CL also filters out any sensitive keys if
getSessionCharactersitics is called from a process that does not have
camera permission granted.

Bug: 303645857
Test: atest android.hardware.camera2.cts.CameraDeviceSetupTest passes
Test: atest android.hardware.camera2.cts.StaticMetadataTest passes
Change-Id: I589c80fc6152ae3cb14c72963953feb94a7f745a