[flexiglass] Sleep, unlock state, and auth method logic changes

1. No longer change scenes if the device becomes unlocked while
   asleep; stay on the lockscreen; we especially don't want to go from
   bouncer to gone while asleep

2. If the auth method changes to a non-secure one, hide the bouncer overlay

Bug: 404470548
Test: unit tests added
Test: manually verified that unlocking the device while its asleep
doesn't move to the gone scene (used adb to change the auth method to a
non-secure one while the device was asleep and observed the
SceneFramework logcat tag to see what scene changes are started in
response)
Test: manually verified that changing the auth method to a non-secure
one while the device is awake and on the bouncer scene correctly hides
the bouncer and returns to the lockscreen scene (using the same method
as above)
Flag: com.android.systemui.scene_container

Change-Id: I7ecc74824adf25b5c05116de783417eb3fa7c85f