feat: a typed QRZ start date fetches that period, not what QRZ edited in it

"Last download" and an operator-chosen date are different questions, and they
now ask QRZ different ones. The automatic run wants everything TOUCHED since it
last ran (MODSINCE) — that is what returns a 2015 QSO confirmed yesterday. A date
typed by the operator names a period of OPERATING, so it maps to BETWEEN date and
today, on the QSO date.

The client-side date filter is skipped only under MODSINCE, where it would throw
away the older-but-newly-confirmed records the query exists to fetch. Under
BETWEEN it agrees with the server and stays on as a backstop.

app.go

@@ -9575,11 +9575,14 @@ func (a *App) runDownloadConfirmations(svc extsvc.Service, cfg extsvc.ExternalSe
 		// QSO date. sinceDate is "YYYY-MM-DD".
 		sinceDate := resolveSince(keyExtQRZLastDownload)
 		emit(fmt.Sprintf("Window: since=%q → resolved date=%q (key %s%s)", since, sinceDate, a.profileScope(), keyExtQRZLastDownload))
-		if sinceDate != "" {
+		// An automatic run ("last") and an operator-chosen date do not mean the
-			emit("Fetching QRZ.com logbook (records modified since " + sinceDate + ")…")
+		// same thing, so they ask QRZ two different questions:
-		} else {
+		//   • "last"        → MODSINCE: everything TOUCHED since the last run,
-			emit("Fetching QRZ.com logbook (full — no since date)…")
+		//                     which is what catches a 2015 QSO confirmed yesterday.
-		}
+		//   • a typed date  → BETWEEN: the QSOs MADE from that date to today. The
+		//                     operator asked for a period of operating, not for
+		//                     whatever QRZ happened to edit in that period.
+		autoWindow := strings.EqualFold(strings.TrimSpace(since), "last")
 		// Ask QRZ for the WINDOW rather than the whole logbook. "ALL" made the
 		// server serialise every QSO — 56 MB for a 117k-record log — which it
 		// truncates mid-record, so the parse died two thirds of the way through
@@ -9595,13 +9598,26 @@ func (a *App) runDownloadConfirmations(svc extsvc.Service, cfg extsvc.ExternalSe
 		//
 		// It stays an optimisation, never a requirement: if QRZ refuses it, fall
 		// back to ALL rather than leaving the operator with no download at all.
+		//
+		// serverWindowed is set only for MODSINCE, because it alone returns QSOs
+		// OLDER than the date — the client-side date filter would drop exactly
+		// those. Under BETWEEN the filter agrees with the server and stays on as a
+		// backstop.
 		fetchOpt, serverWindowed := "ALL", false
-		if sinceDate != "" {
+		switch {
+		case sinceDate == "":
+			emit("Fetching QRZ.com logbook (full — no since date)…")
+		case autoWindow:
 			fetchOpt, serverWindowed = "MODSINCE:"+sinceDate, true
+			emit("Fetching QRZ.com logbook (records modified since " + sinceDate + ")…")
+		default:
+			today := time.Now().UTC().Format("2006-01-02")
+			fetchOpt = "BETWEEN:" + sinceDate + "+" + today
+			emit("Fetching QRZ.com logbook (QSOs from " + sinceDate + " to " + today + ")…")
 		}
 		fr, err := extsvc.FetchQRZ(ctx, nil, cfg.QRZ.APIKey, fetchOpt)
-		if err != nil && serverWindowed {
+		if err != nil && fetchOpt != "ALL" {
-			emit("QRZ.com refused MODSINCE (" + err.Error() + ") — fetching the full logbook instead…")
+			emit("QRZ.com refused " + fetchOpt + " (" + err.Error() + ") — fetching the full logbook instead…")
 			fetchOpt, serverWindowed = "ALL", false
 			fr, err = extsvc.FetchQRZ(ctx, nil, cfg.QRZ.APIKey, fetchOpt)
 		}