Please extract SharedElementTransition

The installation process is hard, and you cannot use `react-native link` anymore, that's a disadvantage, so is there a chance to extract `SharedElementTransition` component to different module so we can use it with other much simpler navigators

Start by locating the SharedElementTransition component and reviewing how it is currently tied to the navigation package and installation process. Extract it into a separate module that can be used with simpler navigators, then verify that the existing navigation use case and the requested standalone use case remain supported.

Written by the indexing model from the issue text.