Record configuration normalization at sequence boundaries

internal/core/config/document_normalizer.go

@@ -0,0 +1,26 @@
+package config
+
+import configkit "gitea.maximumdirect.net/eric/ConfigKit"
+
+// documentNormalizer records leaf provenance and, while visiting a sequence,
+// covers its atomic mutation boundary. ConfigKit audits sequences as whole
+// values, so a record for only a descendant is insufficient. The outermost
+// sequence covers nested sequences as well; unchanged visits record nothing.
+type documentNormalizer struct {
+	*configkit.Resolution
+	sequence *configkit.Path
+}
+
+func (n documentNormalizer) inSequence(path configkit.Path) documentNormalizer {
+	if n.sequence == nil {
+		n.sequence = &path
+	}
+	return n
+}
+
+func (n documentNormalizer) Record(path configkit.Path, kind configkit.ChangeKind, reason string, dependencies ...configkit.Path) {
+	n.Resolution.Record(path, kind, reason, dependencies...)
+	if n.sequence != nil {
+		n.Resolution.Record(*n.sequence, kind, reason, append([]configkit.Path{path}, dependencies...)...)
+	}
+}