Build Department Portal Role and Access Management

**Description**

Create the user access and permission structure for the Department Portal.
The Department Portal will support department-level users who need access to manage their department’s labor information, positions, and personnel.
The platform should distinguish between:

**Department Staff**
- Can view department labor information.
- Can view positions.
- Can submit requests.
**Labor Coordinator**
- Has additional permissions to manage department supervisors and department personnel.

The system should ensure that users have access only to the departments and features they are authorized to manage.

**Expected Functionality**

The platform should allow:
- Departments to view users associated with their department.
- Departments to designate a Labor Coordinator.
- Labor Coordinators to manage supervisor-related permissions.
- Users to be added or removed from departments.

**Requirements Covered**

D-04: Departments can control which users are in their department and designate a Labor Coordinator.

The issue names no files, tests, or entry points. Start by locating the existing department, user, and personnel models and the entry points where role and access checks are defined. Done means the D-04 behaviors are implemented: department membership is manageable, a Labor Coordinator can be designated, and department-scoped permissions are enforced.

Written by the indexing model from the issue text.