Remove unused overlay value snapshots

docs/internal/overview.md

@@ -14,7 +14,8 @@ module and package documentation boundary. Its implemented public primitives are
   definitions, retains ordered claims and composite mapping origins, reports every
   conflicting location, and never aliases an input tree;
 - fixed selected-profile loading in `profile.go` and recursive, non-aliasing overlay
-  with displacement records in `overlay.go`;
+  with displacement records in `overlay.go`; overlay records retain origins,
+  while value explanation uses separate history applications;
 - detached parser-neutral CLI override validation and synthetic-source application
   in `override.go`, sharing overlay, source, byte, node, and depth policies;
 - a per-operation private reflection descriptor graph in `schema.go` for supported

docs/roadmap/remediation.md

@@ -2,7 +2,7 @@
 
 ## Status and scope
 
-Status: planned; no stages have been implemented under this roadmap.
+Status: in progress; completed stages and their validation are recorded below.
 Audit baseline: `9b147bfd96aec25e0125dcae66e136e56dc7a670`.
 
 This roadmap owns the agreed maintainability cleanup before v0.1.0. It replaces
@@ -61,7 +61,13 @@ consumer contracts.
 
 ## Stage 1 — Remove unused overlay value snapshots
 
-Status: pending.
+Status: complete.
+
+Completion: removed unread overlay before/after trees and their construction and
+cloning, including the now-unused CLI position lookup. Field-read review confirmed
+that resolution snapshots and history applications have separate live consumers;
+those and displaced origins remain intact. The full offline test suite, vet,
+build, and whitespace checks passed with Go 1.26.7 on Linux/amd64.
 
 Evidence: `overlayRecord` in [overlay.go](../../overlay.go) retains `before` and
 `after` trees; profile and CLI processing construct them and

overlay.go

@@ -10,8 +10,6 @@ import (
 type overlayRecord struct {
 	change    Change
 	displaced []displacedDefinition
-	before    *document.Node
-	after     *document.Node
 }
 
 type displacedDefinition struct {
@@ -73,7 +71,6 @@ func mergeOverlayMappings(result *composedDocument, target, overlay *document.No
 					Previous: previousOrigins(previous),
 				},
 				displaced: displaced,
-				before:    document.Clone(existing), after: document.Clone(incoming.Value),
 			})
 		}
 	}
@@ -161,8 +158,6 @@ func cloneOverlayRecords(records []overlayRecord) []overlayRecord {
 	cloned := make([]overlayRecord, len(records))
 	for index, record := range records {
 		cloned[index].change = cloneChange(record.change)
-		cloned[index].before = document.Clone(record.before)
-		cloned[index].after = document.Clone(record.after)
 		cloned[index].displaced = make([]displacedDefinition, len(record.displaced))
 		for displacedIndex, displaced := range record.displaced {
 			cloned[index].displaced[displacedIndex] = displacedDefinition{

override.go

@@ -407,14 +407,12 @@ func applyPreparedOverride(result *composedDocument, override preparedOverride)
 
 		previous := cloneOrigin(result.origins[path.String()])
 		var displaced []displacedDefinition
-		var before *document.Node
 		if position < 0 {
 			incoming := document.Clone(override.value)
 			current.Mapping = append(current.Mapping, document.Entry{Key: segment.key, KeyLocation: location, ValueLocation: location, Value: incoming})
 			collectOverlayOrigins(result.origins, incoming, path, LayerCLI)
 		} else {
 			existing := current.Mapping[position].Value
-			before = document.Clone(existing)
 			displaced = affectedOverrideOrigins(existing, override.value, result.origins, path)
 			if existing.Kind == document.Mapping && override.value.Kind == document.Mapping {
 				mergeOverlayOrigin(result.origins, path, location, LayerCLI)
@@ -425,10 +423,9 @@ func applyPreparedOverride(result *composedDocument, override preparedOverride)
 				collectOverlayOrigins(result.origins, current.Mapping[position].Value, path, LayerCLI)
 			}
 		}
-		position = documentEntryIndex(current.Mapping, segment.key)
 		result.overlays = append(result.overlays, overlayRecord{change: Change{
 			Path: path.clone(), Origin: overlayOrigin(LayerCLI, location), Previous: previousOrigins(previous),
-		}, displaced: displaced, before: before, after: document.Clone(current.Mapping[position].Value)})
+		}, displaced: displaced})
 		result.applications = append(result.applications, historyApplication{
 			layer: LayerCLI, path: path.clone(), value: override.value,
 			origin: overlayOrigin(LayerCLI, location),