[lib/native/web] make user profile accessible from a user entity in a robotext

Summary:
This diff introduces a UserEntity component to be used by the InnerRobotextMesssage. UserEntity will be a touchable that wil navigate to the user profile when onPress is triggered

Depends on D9388

Test Plan:
Please see the demo video below

Reviewers: atul, inka

Reviewed By: atul

Subscribers: ashoat, tomek, wyilio

Differential Revision: https://phab.comm.dev/D9389