feat: panadapter spots that read, a CI-V link that survives, no auto-call

Panadapter spots are now worth reading. The comment carries the spotter, the
entity and the status in DXHunter's own shape — "CQ up 2 [F4BPO] [Franz Josef
Land] [New Slot]" — which needed two things nothing documents: SmartSDR splits
its command line on SPACES, so the words ran together until every space became
non-breaking; and it truncates past ~60 characters, so the cluster's own words
are trimmed first and the three brackets always survive. RBN column padding is
collapsed on the way in, or a preserved run of spaces opened a gap wide enough
to push the rest off screen.

"Already worked" means the CALLSIGN is in the log, not the entity: saying it of
a station never contacted was simply wrong. Each status can also be kept off the
panadapter entirely, and the WSJT-X decode spots obey the same switches — the
palette governs the panadapter, not one of the two things that feed it.

And the radio is no longer hammered: a spot whose frequency, colour and comment
are unchanged is not removed and redrawn. A busy skimmer feed re-spots the same
station every few seconds; one two-minute session sent 2128 adds, 88 of them for
a single callsign, and the display did not move a pixel for any of them.

CI-V, from an IC-7850 that kept killing JTDX: a reply the rig sent to another
controller on the same bus is no longer taken for ours, and a set_ptt, set_freq
or set_mode whose acknowledgement goes missing is verified by reading the rig
back instead of being reported as a failure. WSJT-X and JTDX answer a failed
command with a Rig Control Error and drop the link mid-over — 98 keyings, 6 lost
acknowledgements, 2 dropped connections in one session. The check waits 700 ms,
not the poll's 150: the rig has just failed to answer twice because it was
retuning, and a short probe would fail for the same reason.

Auto-call is withdrawn — it duplicated DXHunter, which already answers decodes,
and two programs deciding that from one shack key over each other. The library
is kept whole and dormant; a guard in App.tsx makes sure a stored preference
cannot key a transmitter whose switch no longer exists.

Also:
  - the log rotates while running, not only at startup: the CI-V trace left on
    wrote 416 MB and nothing would have stopped it before the disk did. Closing
    it now releases the crash file too — the runtime keeps its own duplicate.
  - the interface zoom announces itself, with a badge, a click back to 100% and
    a View menu; Ctrl+wheel and Ctrl+0 always worked and nothing said so.
  - no more elastic bounce, and no swipe-to-navigate out of the app.
  - Edit QSO: your own TX power and the contacted station's extended locator
    were saved and written back with no box to set them.
  - FT decodes: continents are a multiple choice; a compound MSHV message that
    answers two stations in one line is recognised as addressed to you.

frontend/src/App.tsx

@@ -1284,11 +1284,22 @@ export default function App() {
   // by z, so it reflows to fill that larger box and then scales back to exactly the
   // window (more content visible when zoomed out, like a real browser zoom).
   const appRootRef = useRef<HTMLDivElement>(null);
+  // The current factor, shown briefly whenever it changes.
+  //
+  // Ctrl+wheel and Ctrl+0 have worked from the start, and NOTHING said so:
+  // no menu entry, no readout. An operator who zoomed by accident — easy, the
+  // wheel is over a grid and Ctrl is already down for something else — saw the
+  // interface change size with no explanation and no way back. The number is
+  // the fix; the menu entry makes it findable without reading a manual.
+  const [uiZoom, setUiZoom] = useState(1);
+  const [zoomShown, setZoomShown] = useState(false);
+  const zoomHideRef = useRef(0);
+  const setZoomRef = useRef<(z: number) => void>(() => {});
   useEffect(() => {
     const KEY = 'opslog.uiZoom';
     let z = parseFloat(localStorage.getItem(KEY) || '1');
     if (!Number.isFinite(z) || z <= 0) z = 1;
-    const apply = () => {
+    const apply = (announce = false) => {
       const el = appRootRef.current;
       if (!el) return;
       el.style.transformOrigin = '0 0';
@@ -1296,17 +1307,36 @@ export default function App() {
       el.style.width = `${100 / z}vw`;
       el.style.height = `${100 / z}vh`;
       document.documentElement.setAttribute('data-uizoom', String(z));
+      setUiZoom(z);
+      // Only on a CHANGE: showing it at startup would put a badge over the log
+      // every launch, for a number that is almost always 100 %.
+      if (announce) {
+        setZoomShown(true);
+        window.clearTimeout(zoomHideRef.current);
+        zoomHideRef.current = window.setTimeout(() => setZoomShown(false), 1600);
+      }
     };
     apply();
+    // The menu and the badge set the factor through here, so there is one
+    // implementation of "zoom to z" and not three.
+    setZoomRef.current = (next: number) => {
+      z = Math.min(2.5, Math.max(0.5, Math.round(next * 10) / 10));
+      localStorage.setItem(KEY, String(z));
+      apply(true);
+    };
     const onWheel = (e: WheelEvent) => {
       if (!e.ctrlKey && !e.metaKey) return; // plain wheel is left alone (scroll / freq nudge)
       e.preventDefault();
       z = Math.min(2.5, Math.max(0.5, Math.round((z + (e.deltaY < 0 ? 0.1 : -0.1)) * 10) / 10));
       localStorage.setItem(KEY, String(z));
-      apply();
+      apply(true);
     };
     const onKey = (e: KeyboardEvent) => {
-      if ((e.ctrlKey || e.metaKey) && (e.key === '0')) { e.preventDefault(); z = 1; localStorage.setItem(KEY, '1'); apply(); }
+      if ((e.ctrlKey || e.metaKey) && (e.key === '0')) { e.preventDefault(); z = 1; localStorage.setItem(KEY, '1'); apply(true); }
+      // Ctrl+plus / Ctrl+minus, the shortcuts every other application uses.
+      // '=' as well as '+': on most layouts the plus is the shifted '='.
+      if ((e.ctrlKey || e.metaKey) && (e.key === '+' || e.key === '=')) { e.preventDefault(); setZoomRef.current(z + 0.1); }
+      if ((e.ctrlKey || e.metaKey) && (e.key === '-')) { e.preventDefault(); setZoomRef.current(z - 0.1); }
     };
     window.addEventListener('wheel', onWheel, { passive: false });
     window.addEventListener('keydown', onKey);
@@ -2274,6 +2304,9 @@ export default function App() {
   const [clusterMacros, setClusterMacros] = useState(loadClusterMacros);
   useEffect(() => { if (!showSettings) setClusterMacros(loadClusterMacros()); }, [showSettings]);
   const clusterMacrosShown = useMemo(() => visibleClusterMacros(clusterMacros), [clusterMacros]);
+  // Auto-call is withdrawn — it duplicated DXHunter, which answers decodes from
+  // the same shack. This flag is the single place that says so at runtime.
+  const AUTO_CALL_ENABLED = false;
   const [autoCall, setAutoCall] = useState<AutoCallSettings>(loadAutoCall);
   useEffect(() => { if (!showSettings) setAutoCall(loadAutoCall()); }, [showSettings]);
   // When each callsign was last answered, so a station still calling CQ is not
@@ -2306,6 +2339,15 @@ export default function App() {
   // backstop below.
   const lastTxAtRef = useRef<Map<string, number>>(new Map());
   useEffect(() => {
+    // AUTO-CALL IS WITHDRAWN — DXHunter already answers decodes, and two
+    // programs doing it from one shack key over each other. See lib/autocall.ts.
+    //
+    // Returning here rather than deleting the loop: the decision it implements
+    // is the delicate part, argued over and tested, and worth keeping intact.
+    // The guard is what matters — an operator whose stored preference still
+    // says "enabled" must not have their transmitter keyed by a feature they
+    // can no longer see, let alone switch off.
+    if (!AUTO_CALL_ENABLED) return;
     if (!autoCall.enabled) return;
     const now = Date.now();
     // A QSO is in progress somewhere if ANY receiver is transmitting or still
@@ -2663,8 +2705,17 @@ export default function App() {
   // Backend-emitted toast messages (e.g. recording auto-send result/skip).
   useEffect(() => {
     const off = EventsOn('toast', (msg: any) => { if (msg) showToast(String(msg)); });
-    return () => { off(); };
-  }, [showToast]);
+    // A QSO logged by an external app announces itself: nothing else on screen
+    // says it happened when the operator is watching the decodes rather than the
+    // entry form.
+    const offExt = EventsOn('qso:logged_external', (p: any) => {
+      const call = String(p?.call ?? '').trim();
+      if (!call) return;
+      const bits = [p?.band, p?.mode].filter(Boolean).join(' · ');
+      showToast(`✅ ${t('toast.qsoLogged')} — ${call}${bits ? ` · ${bits}` : ''}`);
+    });
+    return () => { off(); offExt(); };
+  }, [showToast, t]);
 
   // Band openings — sporadic E on 6/4/2 m, detected from the spot stream.
   //
@@ -4668,6 +4719,10 @@ export default function App() {
       { type: 'item', label: t('edit.prefs'), action: 'edit.prefs' },
     ]},
     { name: 'view', label: t('menu.view'), items: [
+      { type: 'item', label: t('view.zoomIn'), action: 'view.zoomin', shortcut: 'Ctrl++' },
+      { type: 'item', label: t('view.zoomOut'), action: 'view.zoomout', shortcut: 'Ctrl+-' },
+      { type: 'item', label: t('view.zoomReset'), action: 'view.zoomreset', shortcut: 'Ctrl+0' },
+      { type: 'separator' },
       { type: 'item', label: t('view.refresh'), action: 'view.refresh', shortcut: 'F5' },
       { type: 'item', label: t('view.clearFilters'), action: 'view.clearfilters' },
     ]},
@@ -4716,6 +4771,9 @@ export default function App() {
       case 'file.exportCabrillo': exportCabrillo(); break;
       case 'file.deleteall':    setShowDeleteAll(true); break;
       case 'file.exit':         QuitApp(); break;
+      case 'view.zoomin':       setZoomRef.current(uiZoom + 0.1); break;
+      case 'view.zoomout':      setZoomRef.current(uiZoom - 0.1); break;
+      case 'view.zoomreset':    setZoomRef.current(1); break;
       case 'view.refresh':      refresh(); break;
       case 'view.clearfilters': setFilterCallsign(''); setActiveFilter({ conditions: [], match: 'AND' }); break;
       case 'edit.edit':         if (selectedId !== null) openEdit(selectedId); break;
@@ -5812,14 +5870,6 @@ export default function App() {
       txMsgs={txMsgs}
       txState={txState}
       txStates={txStates}
-      autoCallOn={autoCall.enabled}
-      // Written through the same key Preferences uses, so the two can never
-      // disagree about whether the machine is armed.
-      onToggleAutoCall={() => setAutoCall((prev) => {
-        const next = { ...prev, enabled: !prev.enabled };
-        writeUiPref(autoCallKey, JSON.stringify(next));
-        return next;
-      })}
       spotStatus={spotStatus as any}
       myCall={station.callsign}
       // A click ANSWERS the station: it hands the decode back to WSJT-X/MSHV as
@@ -6668,6 +6718,21 @@ export default function App() {
         </div>
       )}
 
+      {/* The zoom factor, while it is changing.
+          Centred at the top, out of the way of the entry form and the toasts,
+          and clickable: the number is only half an answer if the way back to
+          100 % is another thing to know. */}
+      {zoomShown && uiZoom !== 1 && (
+        <button
+          type="button"
+          onClick={() => setZoomRef.current(1)}
+          title={t('view.zoomResetTip')}
+          className="fixed top-2 left-1/2 -translate-x-1/2 z-[130] rounded-full border border-border bg-card/95 px-3 py-1 text-xs font-mono shadow-lg hover:bg-accent"
+        >
+          {Math.round(uiZoom * 100)}% · {t('view.zoomReset')}
+        </button>
+      )}
+
       {/* Transient toasts (bottom-right). Errors stack on top of the green
           success toast; both auto-dismiss. */}
       {/* Unlock encrypted passwords (set via Settings → Security). Dismissable: