Harden item occurrence grounding

internal/modules/dnd/normalize/itemoccurrences/normalizer.go

@@ -68,7 +68,7 @@ func (n *Normalizer) ManifestMetadata() map[string]any {
 	if n == nil || n.itemResolver == nil {
 		return nil
 	}
-	metadata := map[string]any{"normalization_policy": normalizationPolicy}
+	metadata := map[string]any{"normalization_policy": normalizationPolicy, "comparison_policy": shared.TextComparisonPolicy}
 	seeded := n.itemResolver.Seeded()
 	if seeded.Bound() {
 		metadata["item_registry_digest"] = seeded.Digest()
@@ -83,6 +83,7 @@ func (n *Normalizer) CheckpointFingerprints() []pipeline.CheckpointFingerprint {
 	}
 	return []pipeline.CheckpointFingerprint{
 		{Name: "normalization_policy", Value: normalizationPolicy},
+		{Name: "comparison_policy", Value: shared.TextComparisonPolicy},
 		{Name: "item_registry", Value: n.itemResolver.Seeded().ProjectionDigest()},
 	}
 }