3-1/ Impl FoldProvider.FoldCallback for Face enroll activities

Create a mechanism to allow OEM config posture guidance with
'config_face_enroll_guidance_page', and customize the config
'config_face_enroll_supported_posture' with standard postures
         0 : DEVICE_POSTURE_UNKNOWN
         1 : DEVICE_POSTURE_CLOSED
         2 : DEVICE_POSTURE_HALF_OPENED
         3 : DEVICE_POSTURE_OPENED
         4 : DEVICE_POSTURE_FLIPPED
For example, if we set 1 for the device, then device only
allow to enroll face in closed(folded) state, if device do
not in the allow state, we will prompt specific guidance
page activity defined in config_face_enroll_guidance_page.

At this stage , we only integrate 2 states OPENED/CLOSED through
ScreenSizeFoldProvider and register for onFoldUpdated() callback
- isFold(DEVICE_POSTURE_CLOSED): finish posture guidance
- !isFold(DEVICE_POSTURE_OPENED): launch posture guidance
- onActivityResult : reset mOnGuidanceShown false

1. Fix A11y lottie animation bug
2. Impl FoldProvider.FoldCallback
3. Register callback to ScreenSizeFoldProvider
4. Integrate back stack, skip, cancel events
   - Back key : RESULT_CANCELED
   - Skip btn : RESULT_SKIP
   - Posture changed : RESULT_FINISHED
5. Set single instance for relative activities
6. FaceEnrollFoldPage listen for onConfigurationChanged()
7. Add empty face_posture_guidance_lottie.json for overlay

Test: atest SettingsGoogleUnitTests
Test: m -j SettingsGoogleRoboTests RunSettingsGoogleRoboTests
Test: m RunSettingsRoboTests ROBOTEST_FILTER= \
      "com.android.settings.biometrics.face.FaceEnrollEducationTest"
Test: m RunSettingsRoboTests ROBOTEST_FILTER= \
      "com.android.settings.biometrics.face.FaceEnrollIntroductionTest"
Test: Manual launch security settings face enroll, unfold device
and observe posture guidance showing fullscreen on top
Test: Fold device ensure the posture guidance activity finish
Bug: 261141826
Fixes: 231908496

Change-Id: Ib9f43f82f7d19f3f187c2f6f8984e76cd843afbc
Merged-In: Ib9f43f82f7d19f3f187c2f6f8984e76cd843afbc