[BE-03] Create Department entity with TypeORM in opsce module

[yusuftomilola]

Problem

Assets need to be associated with departments but no Department entity exists. Without this, asset grouping and reporting by department is impossible.

Proposed Solution

Create backend/src/opsce/departments/entities/department.entity.ts with a self-referential parent/child relation for department hierarchies.

Acceptance Criteria

• Entity has fields: id (UUID), name (unique), description, code, isActive, createdAt, updatedAt
• @ManyToOne self-referential relation for parent department
• @OneToMany back-reference children departments
• @OneToMany back-reference to Asset entity
• Module and entity registered in OpsceModule

[temiport25]

@temiport25 has applied to work on this issue as part of the Stellar Wave Program's 5th wave.

Can i work on this?

ℹ️ Repo Maintainers: To accept this application, review their application or assign @temiport25 to this issue.

[drips-wave]

Congratulations, @temiport25! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on June 2, 2026.

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