Document PromptKit comparison and catalogs

docs/roadmap/implementation.md

@@ -1,6 +1,6 @@
 # Implement PromptKit comparison and catalogs
 
-Status: Stages 1–9 complete; remaining stages are planned.
+Status: Stages 1–10 complete; remaining stages are planned.
 
 ## Scope and authority
 
@@ -583,6 +583,29 @@ Review diffs, links/fragments, examples, and stale statements; run documented
 Markdown whitespace checks. Describe native semantics as upstream-owned. Do not
 promise arbitrary catalog/provider data is safe for public disclosure.
 
+**Completion evidence (2026-10-12)**
+
+- Updated ckprompt GoDoc for native configuration comparison, all four optional
+  callbacks, callback narrowing, selector/input preparation, nil-factory zero
+  values, and catalog YAML defaults. Root and module READMEs now describe the
+  shipped integration.
+- Updated the CLI reference for PromptKit `config diff` and independent prompt
+  and profile catalogs, including selectors, YAML schema/default, empty results,
+  and the owning-library boundary for comparison and catalog membership. It
+  leaves catalog data disclosure with the application/provider.
+- Updated consumer guidance with a narrowing-before-capture example, the
+  internal package overview, and development commands. The PromptKit roadmap now
+  records delivered behavior; the ConfigKit roadmap summary reflects the later
+  PromptKit adoption; and `deferred.md` retains only requirement inspection as a
+  PromptKit capability deferred from this feature.
+- Reviewed the architecture policy and ADRs 0004 and 0008–0012. They remain
+  consistent with the delivered ownership and invocation model; no decision
+  record changes were needed. Historical baseline and ConfigKit completion
+  records remain clearly scoped to their original work.
+- Markdown whitespace checks passed. A local-link and fragment check passed for
+  all ten changed Markdown files. Composed example behavior was exercised and
+  passed with Stage 9's example and complete ckprompt suite checks.
+
 ## Stage 11: Reconcile notices and prepared release notes
 
 **Outcome:** distributed metadata/notices match actual graphs, and unpublished