In file api, we provide a 'private area' of user, only current user can manage files in this area.
Use case:
1. student uploaded an assignment to private area, then pick up this file in file picker to submit it.
2. teacher uploaded course materials to private area, then use this files in file picker to build a course.
Currently, we can manage all private files at files/index.php, however, it is not straightforward to access and manage.
The user private files browser should be part of my moodle page as a block