Record top-level module metadata in run manifests

internal/core/artifacts/artifacts_test.go

@@ -183,6 +183,42 @@ func TestRunManifestIncludesPipelineAndArtifactLaneFields(t *testing.T) {
 	assertHasKeys(t, lane, "id", "extractor", "merger", "normalizer", "validators", "metadata")
 }
 
+func TestRunManifestIncludesTopLevelModuleMetadata(t *testing.T) {
+	manifest := RunManifest{
+		ModuleMetadata: map[string]map[string]any{
+			"chunker": {
+				"prompt_id":            "dnd.scenes",
+				"prompt_version":       "v1",
+				"prompt_sha256":        "sha256:abc123",
+				"response_schema_key":  "dnd_scenes",
+				"response_schema_name": "dnd_scenes",
+			},
+		},
+	}
+
+	gotJSON, err := json.Marshal(manifest)
+	if err != nil {
+		t.Fatalf("json.Marshal() error = %v", err)
+	}
+
+	var got map[string]any
+	if err := json.Unmarshal(gotJSON, &got); err != nil {
+		t.Fatalf("json.Unmarshal() error = %v", err)
+	}
+
+	moduleMetadata, ok := got["module_metadata"].(map[string]any)
+	if !ok {
+		t.Fatalf("module_metadata = %#v, want object", got["module_metadata"])
+	}
+	assertHasKeys(t, moduleMetadata, "chunker")
+
+	chunkerMetadata, ok := moduleMetadata["chunker"].(map[string]any)
+	if !ok {
+		t.Fatalf("module_metadata.chunker = %#v, want object", moduleMetadata["chunker"])
+	}
+	assertHasKeys(t, chunkerMetadata, "prompt_id", "prompt_version", "prompt_sha256", "response_schema_key", "response_schema_name")
+}
+
 func assertHasKeys(t *testing.T, values map[string]any, keys ...string) {
 	t.Helper()