Audit the public facade boundary

docs/roadmap/public.md

@@ -1,8 +1,8 @@
 # Public facade and internal implementation
 
-Status: agreed direction; not implemented. This roadmap defines the desired end
-state and user intent. The [implementation plan](implementation.md) owns the
-ordered work, concrete adapter design, validation commands, and handoffs.
+Status: implemented on 2026-09-12. This roadmap records the intended architecture
+and user intent; the completed [implementation plan](implementation.md) records
+the ordered work, validation, and handoffs.
 
 ## Intent
 
@@ -31,13 +31,13 @@ design. Existing [configuration contracts](../config.md) and exported Go
 declaration comments remain authoritative. The user-approved wrapper boundary is
 a contributor design choice, not a strengthening of consumer behavior contracts.
 
-## Current architecture
+## Implemented architecture
 
-The root currently owns both public declarations and most private implementation:
-source acquisition, imports, composition and overlays, reflection descriptors,
-decoding, resolution and validation coordination, provenance, history, secret
-handling, and rendering. The [component overview](../internal/overview.md) owns
-the detailed inventory.
+The root owns public declarations, records, wrappers, and deliberate forwarding.
+`internal/engine` owns source acquisition, imports, composition and overlays,
+reflection descriptors, decoding, resolution and validation coordination,
+provenance, history, secret handling, and rendering. The
+[component overview](../internal/overview.md) owns the detailed inventory.
 
 Two established internal boundaries already exist: `internal/document` owns the
 parser-independent tree, and `internal/yaml` owns upstream YAML integration.
@@ -49,7 +49,7 @@ callback state; `Path` holds semantic segments; and `Secret` holds private
 reference and resolved-value state. Moving implementation requires deliberate
 type ownership, not just file relocation.
 
-## Target architecture
+## Architecture
 
 ### Public root package
 
@@ -140,7 +140,7 @@ need to change an established contract requires a separate explicit decision.
 Version selection and publication remain governed by the
 [release policy](../policy/release.md), not by this roadmap.
 
-## Completion criteria
+## Completion evidence
 
 Completion means the root is a legible public surface, substantive plumbing is
 internally owned, consumers require no migration, and representative