feat(hamlog): confirmation defaults and grid columns; drop a settings paragraph

Preferences → Confirmations gains a HAMLOG.online row, sent and received, with
the same defaults every other service has: a new QSO can start at N so the
backlog is meaningful from the first contact. The defaults reach it through a
new setExtraDefault — fill() writes through a pointer to a string field and
these two live in the extras map, which no pointer reaches.

The QSO grid gains four HAMLOG columns (status and date, both directions),
hidden by default: a column per service shown to everyone is how a grid becomes
unreadable.

And the paragraph explaining what "Sent" means is gone from that page.

app.go

@@ -344,6 +344,8 @@ const (
 	keyQSLDefaultHRDLogStatus  = "qsl.hrdlog_status"
 	keyQSLDefaultQRZComStatus  = "qsl.qrzcom_status"
 	keyQSLDefaultQRZComCfm     = "qsl.qrzcom_confirmed"
+	keyQSLDefaultHamlogStatus  = "qsl.hamlog_status"
+	keyQSLDefaultHamlogCfm     = "qsl.hamlog_confirmed"
 
 	// External services (logbook upload). QRZ.com first; Clublog / LoTW
 	// will add their own keys under the same extsvc.* prefix.
@@ -420,6 +422,12 @@ type QSLDefaults struct {
 	HRDLogStatus  string `json:"hrdlog_status"`
 	QRZComStatus  string `json:"qrzcom_status"`
 	QRZComCfm     string `json:"qrzcom_confirmed"` // QRZ.com download/confirmed status
+	// HAMLOG.online lives in the ADIF extras rather than a column — the standard
+	// names a field for hamlog.EU and none for hamlog.ONLINE — but a default is
+	// a default: an operator who uploads everything wants new contacts to start
+	// at "N" here exactly as they do for Club Log.
+	HamlogStatus string `json:"hamlog_status"`
+	HamlogCfm    string `json:"hamlog_confirmed"`
 }
 
 // CATSettings is the user-tweakable rig-control configuration. Stored as
@@ -10521,6 +10529,7 @@ func (a *App) GetQSLDefaults() (QSLDefaults, error) {
 		keyQSLDefaultEQSLSent, keyQSLDefaultEQSLRcvd,
 		keyQSLDefaultClublogStatus, keyQSLDefaultHRDLogStatus,
 		keyQSLDefaultQRZComStatus, keyQSLDefaultQRZComCfm,
+		keyQSLDefaultHamlogStatus, keyQSLDefaultHamlogCfm,
 	)
 	if err != nil {
 		return out, err
@@ -10535,6 +10544,8 @@ func (a *App) GetQSLDefaults() (QSLDefaults, error) {
 	out.HRDLogStatus = m[keyQSLDefaultHRDLogStatus]
 	out.QRZComStatus = m[keyQSLDefaultQRZComStatus]
 	out.QRZComCfm = m[keyQSLDefaultQRZComCfm]
+	out.HamlogStatus = m[keyQSLDefaultHamlogStatus]
+	out.HamlogCfm = m[keyQSLDefaultHamlogCfm]
 	return out, nil
 }
 
@@ -10556,6 +10567,8 @@ func (a *App) SaveQSLDefaults(d QSLDefaults) error {
 		keyQSLDefaultHRDLogStatus:  strings.ToUpper(strings.TrimSpace(d.HRDLogStatus)),
 		keyQSLDefaultQRZComStatus:  strings.ToUpper(strings.TrimSpace(d.QRZComStatus)),
 		keyQSLDefaultQRZComCfm:     strings.ToUpper(strings.TrimSpace(d.QRZComCfm)),
+		keyQSLDefaultHamlogStatus:  strings.ToUpper(strings.TrimSpace(d.HamlogStatus)),
+		keyQSLDefaultHamlogCfm:     strings.ToUpper(strings.TrimSpace(d.HamlogCfm)),
 	} {
 		if err := a.settings.Set(a.ctx, scope+k, v); err != nil {
 			return err
@@ -10606,6 +10619,27 @@ func applyQSLDefaultsTo(q *qso.QSO, d QSLDefaults) {
 	fill(&q.HRDLogUploadStatus, d.HRDLogStatus)
 	fill(&q.QRZComUploadStatus, d.QRZComStatus)
 	fill(&q.QRZComDownloadStatus, d.QRZComCfm)
+	// The extras, which fill() cannot reach: it writes through a pointer to a
+	// string field, and these two are map entries. Only set when the QSO does not
+	// already carry them, which is the same rule fill() applies.
+	setExtraDefault(q, hamlogSentKey, d.HamlogStatus)
+	setExtraDefault(q, award.HamlogQSLKey, d.HamlogCfm)
+}
+
+// setExtraDefault writes a default into an ADIF extras key, leaving an existing
+// value alone. A blank default means "say nothing", not "write an empty string":
+// an empty extra would be carried into every export.
+func setExtraDefault(q *qso.QSO, key, def string) {
+	def = strings.ToUpper(strings.TrimSpace(def))
+	if def == "" {
+		return
+	}
+	if q.Extras == nil {
+		q.Extras = map[string]string{}
+	}
+	if strings.TrimSpace(q.Extras[key]) == "" {
+		q.Extras[key] = def
+	}
 }
 
 // ── External services (logbook upload) ─────────────────────────────────