Move shared checks into validation package

docs/roadmap/implementation.md

@@ -1,6 +1,6 @@
 # Validation model implementation plan
 
-Status: Ready for implementation using incremental API rollout.
+Status: In progress; the shared validation executor is complete.
 
 This plan implements the enabling work in [model.md](model.md), guided by
 [ADR 0003](../adr/0003-declarative-validation.md). It is written for a Luna
@@ -178,6 +178,11 @@ filesystem. Their tests use synthetic trees and local Git repositories.
 
 ## Stage 1: Extract the shared validation executor
 
+**Completion:** Complete. The default Go suite now runs through
+`internal/validation`, candidate capture and callbacks remain in
+`internal/candidate`, and `Check` and `Publish` share the public callback
+adapter.
+
 **Outcome:** One internal owner runs current default validation, with current
 candidate and publication behavior preserved.