Huge performance increase with building.

Using some designs unearthed from building the higher level model, I have brough that design down to the lower level to speed things up. It only took 8 years, but finally, I think I have mastered mult-threading. No more deadlocks, and no more need for waitgroups for everything.

datamodel/low/reference.go

@@ -54,3 +54,16 @@ func (n KeyReference[T]) IsEmpty() bool {
 func (n KeyReference[T]) GenerateMapKey() string {
 	return fmt.Sprintf("%d:%d", n.KeyNode.Line, n.KeyNode.Column)
 }
+
+func IsCircular(node *yaml.Node, idx *index.SpecIndex) bool {
+	if idx == nil {
+		return false // no index! nothing we can do.
+	}
+	refs := idx.GetCircularReferences()
+	for i := range idx.GetCircularReferences() {
+		if refs[i].LoopPoint.Node == node {
+			return true
+		}
+	}
+	return false
+}