Adopt ConfigKit overlays for pipeline selection

internal/manifest/manifest.go

@@ -1,6 +1,7 @@
 package manifest
 
 import (
+	"encoding/json"
 	"strings"
 	"time"
 
@@ -71,13 +72,25 @@ type StageRecord struct {
 // EffectiveConfigProvenance records bounded non-secret configuration identity
 // for one resolved invocation.
 type EffectiveConfigProvenance struct {
-	SelectedProfile       *SelectedProfileProvenance `json:"selected_profile,omitempty"`
+	SelectedOverlay       *SelectedOverlayProvenance `json:"selected_overlay,omitempty"`
 	EffectiveConfigDigest string                     `json:"effective_config_digest,omitempty"`
 }
 
-// SelectedProfileProvenance identifies an explicitly or default-selected
-// pipeline profile without recording profile content.
-type SelectedProfileProvenance struct {
+// UnmarshalJSON accepts unknown informational provenance from older manifests.
+// The enclosing manifest and its execution state remain strictly decoded.
+func (p *EffectiveConfigProvenance) UnmarshalJSON(data []byte) error {
+	type provenance EffectiveConfigProvenance
+	var decoded provenance
+	if err := json.Unmarshal(data, &decoded); err != nil {
+		return err
+	}
+	*p = EffectiveConfigProvenance(decoded)
+	return nil
+}
+
+// SelectedOverlayProvenance identifies an explicitly or default-selected
+// pipeline overlay without recording overlay content.
+type SelectedOverlayProvenance struct {
 	Name   string `json:"name"`
 	Source string `json:"source"`
 }

internal/manifest/store_test.go

@@ -34,7 +34,7 @@ func TestLocalStoreCreateSaveLoadRoundTrip(t *testing.T) {
 	m.S3SessionPrefix = "dnd/campaigns/forsaken/sessions/2026-05-03/"
 	m.S3RunPrefix = "dnd/campaigns/forsaken/sessions/2026-05-03/runs/20260515T031522Z-a1b2c3d4/"
 	m.EffectiveConfig = &EffectiveConfigProvenance{
-		SelectedProfile:       &SelectedProfileProvenance{Name: "production", Source: "default"},
+		SelectedOverlay:       &SelectedOverlayProvenance{Name: "production", Source: "default"},
 		EffectiveConfigDigest: "001122",
 	}
 
@@ -57,7 +57,7 @@ func TestLocalStoreCreateSaveLoadRoundTrip(t *testing.T) {
 	if loaded.RunID != "20260515T031522Z-a1b2c3d4" {
 		t.Fatalf("RunID = %q, want run id", loaded.RunID)
 	}
-	if loaded.EffectiveConfig == nil || loaded.EffectiveConfig.SelectedProfile == nil || loaded.EffectiveConfig.SelectedProfile.Name != "production" || loaded.EffectiveConfig.EffectiveConfigDigest != "001122" {
+	if loaded.EffectiveConfig == nil || loaded.EffectiveConfig.SelectedOverlay == nil || loaded.EffectiveConfig.SelectedOverlay.Name != "production" || loaded.EffectiveConfig.EffectiveConfigDigest != "001122" {
 		t.Fatalf("effective config provenance = %#v", loaded.EffectiveConfig)
 	}
 	stage, ok := loaded.Stages["prepare"]
@@ -75,6 +75,21 @@ func TestLocalStoreCreateSaveLoadRoundTrip(t *testing.T) {
 	}
 }
 
+func TestLocalStoreLoadsManifestWithHistoricalSelectionProvenance(t *testing.T) {
+	path := filepath.Join(t.TempDir(), "manifest.json")
+	data := `{"schema_version":"narratio.session-manifest.v1","session_id":"2026-05-03","created_at":"2026-05-03T10:00:00Z","updated_at":"2026-05-03T10:00:00Z","effective_config":{"selected_profile":{"name":"testing","source":"explicit"},"effective_config_digest":"001122"},"stages":{}}`
+	if err := os.WriteFile(path, []byte(data), 0o600); err != nil {
+		t.Fatal(err)
+	}
+	loaded, err := (&LocalStore{}).Load(context.Background(), path)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if loaded.EffectiveConfig == nil || loaded.EffectiveConfig.EffectiveConfigDigest != "001122" || loaded.EffectiveConfig.SelectedOverlay != nil {
+		t.Fatalf("historical informational provenance = %#v", loaded.EffectiveConfig)
+	}
+}
+
 func TestLocalStorePreservesOptionalArtifactMetadata(t *testing.T) {
 	store := &LocalStore{}
 	ctx := context.Background()