As a team lead, I want to assign different levels of access and permissions to team members so that sensitive information is protected and only authorized users can make changes.
Acceptance Criteria:
* Users can be assigned different roles (e.g., viewer, editor, admin).
* Each role has specific permissions (e.g., view-only, edit, manage users).
* Users can change roles and permissions as needed.
* The system logs all access and changes made by each user.
* Notifications are sent when roles or permissions are changed.
* A summary of user roles and permissions is available for review.
* Users can request changes to their access level.
Sample Expected Result:
Role-Based Access Control for Proposal #12345:
| Team Member | Role   | Permissions           |
|-------------|--------|-----------------------|
| Alice       | Admin  | Full access           |
| Bob         | Editor | Edit content          |
| Charlie     | Viewer | View only             |