Adopt ConfigKit overlays for pipeline selection

internal/config/load.go

@@ -15,14 +15,14 @@ func LoadPipeline(path string) (*PipelineConfig, error) {
 	return LoadPipelineWithOptions(path, PipelineLoadOptions{})
 }
 
-// PipelineLoadOptions carries an optional explicit profile selection. Nil,
+// PipelineLoadOptions carries an optional explicit overlay selection. Nil,
 // empty, and the exact name "default" select the base configuration.
 type PipelineLoadOptions struct {
-	Profile *string
+	Overlay *string
 }
 
 // LoadPipelineWithOptions loads pipeline configuration with strict field
-// checking and optional named-profile selection.
+// checking and optional named-overlay selection.
 func LoadPipelineWithOptions(path string, opts PipelineLoadOptions) (*PipelineConfig, error) {
 	cfg, err := loadPipelineWithConfigKit(path, opts)
 	if err != nil {
@@ -31,20 +31,20 @@ func LoadPipelineWithOptions(path string, opts PipelineLoadOptions) (*PipelineCo
 	return finalizeLoadedPipeline(path, cfg)
 }
 
-// LoadPipelineProfilePair resolves two profiles as independent ConfigKit loads.
-func LoadPipelineProfilePair(path, leftProfile, rightProfile string) (*PipelineConfig, *PipelineConfig, error) {
-	if leftProfile == rightProfile {
-		return nil, nil, fmt.Errorf("load pipeline profiles: left and right profile selections must differ")
+// LoadPipelineOverlayPair resolves two overlays as independent ConfigKit loads.
+func LoadPipelineOverlayPair(path, leftOverlay, rightOverlay string) (*PipelineConfig, *PipelineConfig, error) {
+	if leftOverlay == rightOverlay {
+		return nil, nil, fmt.Errorf("load pipeline overlays: left and right overlay selections must differ")
 	}
-	leftOptions := PipelineLoadOptions{Profile: &leftProfile}
-	rightOptions := PipelineLoadOptions{Profile: &rightProfile}
+	leftOptions := PipelineLoadOptions{Overlay: &leftOverlay}
+	rightOptions := PipelineLoadOptions{Overlay: &rightOverlay}
 	left, err := LoadPipelineWithOptions(path, leftOptions)
 	if err != nil {
-		return nil, nil, fmt.Errorf("load left pipeline profile: %w", err)
+		return nil, nil, fmt.Errorf("load left pipeline overlay: %w", err)
 	}
 	right, err := LoadPipelineWithOptions(path, rightOptions)
 	if err != nil {
-		return nil, nil, fmt.Errorf("load right pipeline profile: %w", err)
+		return nil, nil, fmt.Errorf("load right pipeline overlay: %w", err)
 	}
 	return left, right, nil
 }
@@ -76,7 +76,7 @@ func LoadSession(path string) (*SessionConfig, error) {
 type SessionLoadOptions struct {
 	SessionID         string
 	PreviousSessionID string
-	Profile           *string
+	Overlay           *string
 }
 
 // LoadSessionWithOptions loads session configuration from a YAML file with
@@ -143,7 +143,7 @@ func Load(pipelinePath string, paths ...string) (*Config, error) {
 // LoadWithSessionOptions loads and resolves combined pipeline, campaign, and
 // session configuration with expected session identity checks.
 func LoadWithSessionOptions(pipelinePath, campaignPath, sessionPath string, sessionOpts SessionLoadOptions) (*Config, error) {
-	pipelineCfg, err := LoadPipelineWithOptions(pipelinePath, PipelineLoadOptions{Profile: sessionOpts.Profile})
+	pipelineCfg, err := LoadPipelineWithOptions(pipelinePath, PipelineLoadOptions{Overlay: sessionOpts.Overlay})
 	if err != nil {
 		return nil, err
 	}