Mark chunk plan implementation complete

docs/roadmap/implementation.md

@@ -4,12 +4,9 @@ This document records the implementation of the target state in
 [ADR-0005 Feature Roadmap](adr0005.md), governed by
 [ADR-0005](../adr/0005-cache-canonical-chunk-plans-by-source.md).
 
-Stages 1 through 8 summarize the completed initial implementation. Stages 9
-through 12 record remediation identified by the post-implementation review and
-retain their individual completion status. Current behavior is documented in the
-canonical references linked from [Development](../development.md); those
-references must not describe a remediation target state until its corresponding
-work is complete.
+All stages are complete. This document remains a concise historical
+implementation record. Current behavior is documented in the canonical
+references linked from [Development](../development.md).
 
 ## Execution Rules
 
@@ -409,7 +406,7 @@ remain correctly classified, and all focused and repository-wide checks pass.
 
 ## Stage 10: Enforce rooted chunk-plan filesystem access
 
-**Status:** Pending
+**Status:** Complete
 
 ### Objective
 
@@ -527,7 +524,7 @@ current materialized bytes remain stable; and all checks pass.
 
 ## Stage 12: Finalize remediation documentation and roadmap status
 
-**Status:** Pending
+**Status:** Complete
 
 ### Objective