Pixiportal

As an administrator, I want to manage departments, so that the company's organizational structure remains centralized.

- Acceptance Criteria:
Creation:
The administrator can create a department with a unique name.

Modification:
The administrator can rename an existing department; the change propagates to all related user profiles.

Deactivation:
The administrator can deactivate a department. It is no longer offered when creating/editing a user, but already-linked users retain the information. Departments are deactivated, never deleted.

Dependencies:
A department cannot be deactivated while it still contains active teams; a message indicates this.