feat(A11yFeedback): Add feedback entry for framework accessibility

This entry point allows users to access in the action bar.
Visibility is controlled by the aconfig and FeedbackManager#isAvailable

Bug: 393980229
Test: Manual testing on Pixel and non-Pixel devices
Test: atest BaseSupportFragmentTest
            BaseRestrictedSupportFragmentTest
Flag: com.android.server.accessibility.enable_low_vision_generic_feedback
Change-Id: I47892bd21a7a4e2a4245f5ae61022c2a332b8bbf