[AnimLib] Rename interfaces related to view transition registry

* Rename "IViewTransitionRegistry" interface to "ViewTransitionRegistry"
* Rename "ViewTransitionRegistry" concrete class to
  "ViewTransitionRegistryImpl"
* This renaming is needed as interface names starting with "I" is
  reserved for aidl interfaces

Test: NONE renaming classes only
Bug: 393241010
Flag: com.android.systemui.decouple_view_controller_in_animlib
Change-Id: If5b19890314b48a91bb31d2415f547ec83363d51