Switch CLI configuration to ConfigKit

docs/internal/adapters.md

@@ -18,6 +18,10 @@ described by its tagged
 - `internal/adapter/cli` resolves settings through `internal/config`,
   constructs `promptkit.Engine`, maps CLI values to `promptkit.RunRequest`,
   and owns output files, summaries, and exit codes.
+- `internal/config` delegates application YAML decoding, default resolution,
+  overrides, and validation ordering to ConfigKit. The CLI supplies only
+  explicitly visited application flags as overrides and renders safe structured
+  load diagnostics on stderr.
 - `internal/adapter/http` strictly decodes request DTOs, maps them to Promptkit
   public values, calls its adapter-owned `Runner` interface, and maps results
   and errors to HTTP DTOs.
@@ -53,7 +57,7 @@ not require prompt, schema, or artifact sources.
 with `promptkit.WithArtifactReader`, passes the engine through the HTTP
 adapter's consumer-owned `Runner` interface, and starts the server.
 
-All three CLI paths assemble the engine from the same resolved prompt, profile,
+The command paths assemble the engine from the same resolved prompt, profile,
 and schema directories plus configured custom backends. Each backend is mapped
 to Promptkit's public `Backend` value and registered during engine construction,
 so one constructed server engine retains one immutable backend registry and its

docs/internal/sources.md

@@ -24,9 +24,9 @@ The [configuration reference](../config.md) owns Scriptorium's source-location
 fields and precedence. Maintained files under `examples/` are application
 inputs that use Promptkit's tagged formats.
 
-## Native Application Definition In Preparation
+## Application Configuration Boundary
 
-`internal/config` also contains a ConfigKit-native `Document` definition. Its
+`internal/config` contains a ConfigKit-native `Document` definition. Its
 fresh defaults come from Scriptorium's existing default constants; its resolver
 records only actual trimming, path cleaning, and render-format normalization.
 The validator reports application retry, size-limit, and format errors without
@@ -34,7 +34,7 @@ mutating the document or exposing rejected values. Application path values keep
 working-directory-relative meaning. ConfigKit owns strict YAML decoding and
 presence semantics, including dynamic integer values in backend parameters.
 
-The new `Load` boundary selects an explicit file, the first existing implicit
+The `Load` boundary selects an explicit file, the first existing implicit
 configuration file, or ConfigKit's defaults-only source. Only absence advances
 implicit discovery. One ConfigKit load applies explicit application overrides
 before validation and returns a result containing the resolved document and
@@ -43,9 +43,10 @@ existing runtime settings with backend IDs sorted; it does not read files or
 apply another merge. Imports and selected overlays remain disabled until their
 own user-facing integration is ready.
 
-The executable commands still use the existing loader. The new definition is
-internal preparation and is not yet an alternative user-selectable configuration
-mode or a change to the current [configuration contract](../config.md).
+Every configuration-loading command uses this boundary. The CLI maps only
+explicitly visited application flags to ConfigKit overrides and prints
+structured load diagnostics before engine construction. The old application
+YAML decoder and merge path have been removed.
 
 ## Restricted HTTP Artifact Reader
 
@@ -78,7 +79,8 @@ codes.
 
 Inspect:
 
-- `internal/config/config_test.go`
+- `internal/config/document_test.go`
+- `internal/config/load_test.go`
 - `internal/adapter/cli/run_test.go`
 - `internal/adapter/http/artifact_reader_test.go`
 - `internal/adapter/http/handler_test.go`