Replace department-portal allocation summary with the shared allocation-utilization service

[DanielRukwasha]

Background

PR #654 adds an Allocation card to the Department Portal. The card currently uses app/logic/allocation_utilization.py as a temporary local calculation layer while the official shared allocation-utilization service is being developed.

Work needed

• Replace the calculations in app/logic/allocation_utilization.py with calls to the official shared service.
• Preserve the values required by the Department Portal: total allocated positions, usage by primary/secondary hour bucket, total used positions, and break hours used.
• Confirm which Labor Status Forms should count as used.
• Add or update integration tests.

Acceptance criteria

• The Department Portal does not contain its own allocation-utilization query logic.
• allocation_utilization.py delegates to the official shared service.
• The Allocation card displays correct values for the open term.
• Tests cover the shared-service integration.

Related work

• Parent feature: PR changes in new-allocation-card #654
• Temporary implementation: app/logic/allocation_utilization.py