Carry optional prompt labels through results

internal/observation/recorder.go

@@ -34,7 +34,7 @@ type Recorder struct {
 // Selection contains resolved identities only. Unresolved fields stay empty.
 type Selection struct {
 	PromptID      string
-	PromptVersion string
+	PromptVersion *string
 	ProfileID     string
 	BackendID     string
 	Model         string
@@ -103,7 +103,10 @@ func (r *Recorder) Start() {
 }
 
 // UpdateSelection replaces the known resolved identities for later events.
-func (r *Recorder) UpdateSelection(selection Selection) { r.selection = selection }
+func (r *Recorder) UpdateSelection(selection Selection) {
+	selection.PromptVersion = copyStringPointer(selection.PromptVersion)
+	r.selection = selection
+}
 
 // Attempt records one completed acquisition and optional dispatch.
 func (r *Recorder) Attempt(data AttemptData) {
@@ -177,11 +180,19 @@ func (r *Recorder) Finish(data FinishData) {
 func (r *Recorder) event(kind domain.ExecutionEventKind) domain.ExecutionEvent {
 	return domain.ExecutionEvent{
 		Kind: kind, RunID: r.runID, Time: r.now(), PromptID: r.selection.PromptID,
-		PromptVersion: r.selection.PromptVersion, ProfileID: r.selection.ProfileID,
+		PromptVersion: copyStringPointer(r.selection.PromptVersion), ProfileID: r.selection.ProfileID,
 		BackendID: r.selection.BackendID, Model: r.selection.Model,
 	}
 }
 
+func copyStringPointer(value *string) *string {
+	if value == nil {
+		return nil
+	}
+	copy := *value
+	return &copy
+}
+
 func (r *Recorder) deliver(event domain.ExecutionEvent) {
 	if r.observer != nil {
 		r.observer(event)

internal/observation/recorder_test.go

@@ -50,7 +50,8 @@ func TestRecorderAccountsDispatchedAttemptsAndReportedUsage(t *testing.T) {
 	var events []domain.ExecutionEvent
 	recorder := newRecorder("run-1", now, func(event domain.ExecutionEvent) { events = append(events, event) })
 	recorder.Start()
-	recorder.UpdateSelection(Selection{PromptID: "prompt", PromptVersion: "v1", ProfileID: "profile", BackendID: "backend", Model: "model"})
+	version := "v1"
+	recorder.UpdateSelection(Selection{PromptID: "prompt", PromptVersion: &version, ProfileID: "profile", BackendID: "backend", Model: "model"})
 	recorder.Attempt(AttemptData{
 		Generation: 1, Attempt: 1, Dispatched: true,
 		CapacityWait: 2 * time.Millisecond, GenerationDuration: 10 * time.Millisecond,