Carry optional prompt labels through results

internal/domain/smoke_diagnostics.go

@@ -65,7 +65,7 @@ type SmokeTestTarget struct {
 	BackendID              string
 	ProfileID              string
 	PromptID               string
-	PromptVersion          string
+	PromptVersion          *string
 	DefaultSourceBackendID string
 	SelectionSource        string
 	Endpoint               string
@@ -180,6 +180,7 @@ func CloneSmokeTestRequest(request SmokeTestRequest) (SmokeTestRequest, error) {
 func CloneSmokeTestReport(report SmokeTestReport) (SmokeTestReport, error) {
 	cloned := report
 	cloned.Applicable = cloneBool(report.Applicable)
+	cloned.Target.PromptVersion = cloneString(report.Target.PromptVersion)
 	cloned.Facts = cloneSmokeTestFacts(report.Facts)
 	cloned.Timing = cloneSmokeTestTiming(report.Timing)
 	var err error