Complete documentation reconciliation and validation

docs/roadmap/implementation.md

@@ -860,6 +860,23 @@ post-change measurements are recorded without new performance guarantees, and
 no unapproved feature/policy/dependency changes or temporary harnesses are left
 in the repository. Follow normal commit policy; release preparation remains separate.
 
+Completion: all catalog entries are covered by the implementation and focused
+evidence recorded above, including comparable measurements for the selected
+optimizations. With Go 1.27.3, `GOTOOLCHAIN=local`, and `GOWORK=off`, the full
+offline `go test -race ./...` and `go vet ./...` passed. Tracked Go files are
+formatted; the diff has no whitespace errors; local Markdown targets and headings
+in changed documentation were checked. No benchmark overlays were retained in
+the repository. Release preparation, version selection, tagging, and publication
+remain separate work.
+
+Migration summary: successful artifact readers transfer returned mutable storage;
+convenience sources use ConfigKit's supported value forms; JSON Schemas must be
+self-contained; authentication overflow has an explicit diagnostic reason; and
+opaque prompt definition hashes may change, requiring cross-version caches or
+comparisons to be refreshed. See the [consumer guide](../consumers/pkg-promptkit.md),
+[migration guidance](../consumers/configuration-migration.md), and
+[format reference](../formats.md) for the applicable contracts.
+
 ## Catalog Coverage
 
 | Catalog finding | Owning stages |