Tech debt: JPA entities missing equals/hashCode

[Brad-Edwards]

Description

Requirement, RequirementRelation, and TraceabilityLink have no equals()/hashCode() implementations. They rely on JPA's default object identity, which is fragile:

• Two detached Requirement instances with the same id are not equal in a Set
• AnalysisService.impactAnalysis() returns Set<Requirement> — deduplication relies on object identity, not business identity
• Collection membership checks are unreliable across JPA session boundaries

Recommendation: Implement equals/hashCode based on the business key (uid for Requirement, natural key composite for RequirementRelation and TraceabilityLink).

Location: Requirement.java, RequirementRelation.java, TraceabilityLink.java

Traced Requirements

• GC-A001: Requirement Creation

Impact

Correctness — subtle bugs in set operations, deduplication, and caching.