Use ConfigKit mapping values directly

docs/consumers/pkg-promptkit.md

@@ -178,7 +178,12 @@ input := configkit.Input{Source: document}
 ```
 
 `ProfileSource` and `BackendSource` are smaller typed conveniences when null
-is not needed. Backend and profile definitions are supplied by the caller;
+is not needed. Their provider maps use ConfigKit Mapping input forms: built-in
+scalars, `[]any`, and `map[string]any` recursively. Convert `json.Number` or
+typed containers explicitly to an appropriate supported value, choosing numeric
+precision for your application. Mapping captures supported values immediately;
+unsupported or cyclic values are reported when loaded. Runtime override values
+follow their separate rules. Backend and profile definitions are supplied by the caller;
 there is no registration-only backend namespace.
 
 When configuration or message files change, build and validate a new engine,

docs/roadmap/implementation.md

@@ -93,6 +93,10 @@ source-helper GoDoc and source/construction contract tests.
 capture and deferred upstream diagnostics, not acceptance of `json.Number`,
 typed containers, named scalars, or nested pointers by the removed adapter.
 
+Completion: convenience sources pass provider maps directly to ConfigKit;
+the converter was removed. Focused source and construction tests passed with
+Go 1.27.3, including nested capture and deferred unsupported/cyclic errors.
+
 ## Stage 3: Represent The Owning Error Operation
 
 **Catalog:** 7, first part. **Files:** use-case error/runner/preparation boundaries.