Localize history selection to affected paths

internal/engine/history_source.go

@@ -192,26 +192,25 @@ func sourceApplicationOrigin(application historyApplication, node *document.Node
 }
 
 func sourceOriginRepresentedByOperation(model *historyModel, path Path, origin Origin) bool {
-	represented := false
-	model.reportedPathIndex.visitAncestors(path.String(), func(observationID int) {
+	for _, observationID := range model.observationsByPointer[path.String()] {
 		observation := model.observations[observationID]
 		if observation.phase != historyPhaseSources || observation.role != historyRoleOperation {
-			return
+			continue
 		}
 		if !observation.afterPresent || !sameConcreteHistoryPath(path, observation.path) {
-			return
+			continue
 		}
 		operationOrigin, ok := model.resolveAttribution(observation.attributionRef)
 		if !ok {
-			return
+			continue
 		}
 		if originRepresentedByChange(path, origin, Change{
 			Path: observation.reportedPath, Origin: operationOrigin.origin,
 		}) {
-			represented = true
+			return true
 		}
-	})
-	return represented
+	}
+	return false
 }
 
 func originRepresentedByChange(path Path, origin Origin, change Change) bool {