fix(rotator): put the SP/LP readout inside the compass itself

It went under the Station Control rotator; the compass that wanted it is the
docked one beside the entry strip. Both are the same RotorCompass, so the
readout moves INTO that component: every compass in the app carries it, and no
caller draws its own.

The bezel already showed the short path as a red marker, but a marker is a
direction, not a number — and the numbers in the status bar are 10px, which is
what prompted this.

Clickable only when the caller passed onGoto, since a compass rendered without
one cannot turn anything and a button that does nothing is worse than a label.

hrdlogonair.go

@@ -0,0 +1,74 @@
+package main
+
+// HRDLog "ON AIR" — publishing the live frequency, mode and rig on hrdlog.net,
+// so the site shows "F4BPO is on air 14,074,000 FT8 IC-7300" while the station
+// is operating.
+//
+// The endpoint and its field names come from HRDLog's own library
+// (github.com/iw1qlh/HRDLOG-net-library), not from reading someone's traffic.
+
+import (
+	"context"
+	"strings"
+	"time"
+
+	"hamlog/internal/applog"
+	"hamlog/internal/extsvc"
+)
+
+// onAirEvery is how often the status is refreshed. HRDLog drops a station from
+// the on-air list when it stops hearing from it, so this is a heartbeat, not a
+// change notification.
+const onAirEvery = 2 * time.Minute
+
+// hrdlogOnAirLoop publishes while the option is on and the rig is readable.
+func (a *App) hrdlogOnAirLoop() {
+	defer func() { _ = recover() }() // never crash the app from a status broadcast
+	t := time.NewTicker(onAirEvery)
+	defer t.Stop()
+	for range t.C {
+		a.publishHRDLogOnAir()
+	}
+}
+
+// publishHRDLogOnAir sends one update. Silent when switched off, unconfigured,
+// or when the rig has nothing to report — an announcement with no frequency
+// would say the operator is on air on 0 Hz.
+func (a *App) publishHRDLogOnAir() {
+	cfg := a.loadExternalServices().HRDLog
+	if !cfg.OnAir || strings.TrimSpace(cfg.Callsign) == "" || strings.TrimSpace(cfg.Code) == "" {
+		return
+	}
+	if a.cat == nil {
+		return
+	}
+	st := a.cat.State()
+	if !st.Connected || st.FreqHz <= 0 {
+		return
+	}
+	// The rig NAME as the operator knows it — that string is what the site
+	// displays. The active profile's MyRig first, since it is what every QSO is
+	// stamped with; the CAT backend's own model only when the profile has none.
+	radio := ""
+	if a.profiles != nil {
+		if pr, err := a.profiles.Active(a.ctx); err == nil {
+			radio = strings.TrimSpace(pr.MyRig)
+		}
+	}
+	if radio == "" {
+		radio = strings.TrimSpace(st.Rig)
+	}
+
+	ctx, cancel := context.WithTimeout(context.Background(), 20*time.Second)
+	defer cancel()
+	msg, err := extsvc.SendHRDLogOnAir(ctx, nil, cfg.Callsign, cfg.Code, st.FreqHz, st.Mode, radio)
+	if err != nil {
+		// Logged, never surfaced: this is a broadcast the operator did not ask
+		// for at this instant, and a toast every two minutes on a flaky link
+		// would be worse than the missing status.
+		applog.Printf("hrdlog on-air: %v (%s)", err, msg)
+		return
+	}
+	applog.Printf("hrdlog on-air: %s %.3f MHz %s (%s) — %s",
+		cfg.Callsign, float64(st.FreqHz)/1e6, st.Mode, radio, msg)
+}