Install command batches through one path

docs/roadmap/implementation.md

@@ -1,6 +1,6 @@
 # Implement the optional integration modules and captured registration API
 
-Status: implementation in progress. Stages 1 through 5 are complete; subsequent work follows the ordered roadmap.
+Status: implementation in progress. Stages 1 through 6 are complete; subsequent work follows the ordered roadmap.
 Execute the stages in order. Each stage is sized as a separate Luna coding-agent
 assignment. This document authorizes no publication or changes to sibling
 repositories.
@@ -321,10 +321,14 @@ for routing snapshot/session consolidation.
    `configRegistered`, integration collision prechecks, and root namespace
    allowlists. Integration factories install through the public declaration path.
 
-**Completion evidence:** conflicting roots in either order, invalid final batch
-member, nested root-only commands, no-op errors, explicit absence, empty real
-groups, and declaration reuse across two apps. Inspect that registry writes have
-one boundary, without making its private name a public contract.
+**Completion evidence — complete:** `New` now submits real help/version
+commands and caller declarations to the same private batch installer used by
+`Register`. Retained errors are checked before absence; nested root-only placement,
+root/batch collisions, and invalid final members fail before registry mutation.
+No-op-only registration leaves the cached tree intact; real empty groups and
+reused declarations install correctly. Direct built-in writes, placeholders,
+`configRegistered`, and the registry reservation flag were removed. Registry
+mutation now has one boundary. Root tests pass.
 
 ## Stage 7: Connect neutral routing, Cobra sessions, and execution