feat(iace): benchmark distance panel (Thema 1)

Surface result.distances in the benchmark module: a DistanceComparison
panel showing agreement %, covered values (green), GT-only gaps (amber)
and engine-only extras — mirroring the RiskComparison panel.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

admin-compliance/app/sdk/iace/[projectId]/benchmark/_hooks/useBenchmark.ts

@@ -66,6 +66,21 @@ export interface RiskAgreement {
   high_confidence_pct: number
 }
 
+export interface DistanceToken {
+  value: number
+  unit: string // "mm" | "mm/s"
+  raw: string
+}
+
+export interface DistanceComparison {
+  gt_count: number
+  matched_count: number
+  agreement_pct: number
+  matched: DistanceToken[]
+  gt_only: DistanceToken[]
+  engine_only: DistanceToken[]
+}
+
 export interface BenchmarkResult {
   coverage_score: number
   measure_coverage: number
@@ -78,6 +93,7 @@ export interface BenchmarkResult {
   risk_rank_pairs: { gt_rank: number; engine_rank: number; hazard_name: string; gt_risk_score: number }[]
   risk_comparison?: RiskComparisonPair[]
   risk_agreement?: RiskAgreement
+  distances?: DistanceComparison
 }
 
 interface UseBenchmarkReturn {