fix: log when an in-progress recording is discarded

"No recording was running at log time" says the take had already ended, but not
who ended it. The only path that does is the callsign being cleared — which also
happens when a clicked spot replaces it — and that path was silent.

Now it names itself, so the log shows the moment the recording was lost instead
of only its absence at the end.

app.go

@@ -7777,6 +7777,13 @@ func (a *App) QSOAudioPlayOnAir() error {
 // abandoned without logging).
 func (a *App) QSOAudioCancel() {
 	if a.qsoRec != nil {
+		// Say so when a take is actually thrown away. This fires when the callsign
+		// is cleared — including when a clicked spot replaces it — and until now
+		// it was silent, so a recording that vanished mid-QSO left the log showing
+		// only its absence at save time.
+		if a.qsoRec.Active() {
+			applog.Printf("qso-rec: in-progress recording discarded (callsign cleared)")
+		}
 		a.qsoRec.DiscardQSO()
 	}
 	a.stopManualQSORecorder()