feat(ui): the FT decodes panel, two DXHunter themes, and the maps

Decodes:
- one click SELECTS, two transmit. A single click handed the decode
  straight to WSJT-X as a reply, so brushing a row while reading the
  band started calling a station.
- the list empties for a receiver that changes band, and a receiver
  column appears when more than one is feeding one merged list.
- the period clock turns red while transmitting: it is the one thing on
  the screen that moves, so it is where the eye already is.
- a WL badge, after the LoTW "L" — one letter, always in the same
  place, so the column does not shift from row to row.
- the auto-call switch, its target and its count, and the chase list:
  naming the station you are waiting for is done while watching the
  band, not in a settings tree.

Themes: DXHunter's slate with its own blue, and the same slate with
OpsLog's orange. Counted across its sources rather than guessed from
one panel — blue is 132 uses to violet's 25, and the violet is the PSK
Reporter panel alone.

Watchlist: drawn as DXHunter draws it — the callsign in the interface
font rather than monospaced, which is the difference that shows with
the two windows side by side.

FT Map: arcs no longer run off the side of the map. The map shows one
world, and a path crossing the antimeridian was drawn past 180° into
the blank space beside it — from VK that is most of them.

Cluster: "superfox", "fox/hound" and "F/H" in a comment are read as
FT8. They are WSJT-X's DXpedition transmit modes, and the comment fell
through to the band plan and came out DATA — which then decided the
band+mode verdict.

A decoder is named by what it IS: Nexus sends its packets as "Tempo",
the engine inside it, and OpsLog showed a program nobody has heard of.

frontend/src/App.tsx

@@ -54,7 +54,7 @@ import {
   GetFlexState, FlexAmpOperate,
   GetPSKReporterStatus, GetLiveOpenings, GetChaseNew,
   QSLViaRepairStatus, RepairQSLVia, DismissQSLViaRepair,
-  GetAutoCallStatus, SetAutoCall, SetAutoCallOnly, TakeAutoCallTarget, ResetAutoCall,
+  GetAutoCallStatus, SetAutoCall, SetAutoCallOnly, TakeAutoCallTarget, HaltAutoCall, WatchlistEntries,
 } from '../wailsjs/go/main/App';
 import { Combobox } from '@/components/ui/combobox';
 import { applyAwardRefs, parseAwardRefs as parseManualRefs, spotRefList , withIOTARef, withRDARef } from '@/lib/awardRefs';
@@ -123,6 +123,7 @@ import { GridSquareMap } from '@/components/GridSquareMap';
 import { loadClusterMacros, visibleClusterMacros } from '@/lib/clusterMacros';
 import { DecodesPanel, type Decode as DecodeRow, type TxMsg as TxMsgRow } from '@/components/DecodesPanel';
 import { PSKReporterPanel } from '@/components/PSKReporterPanel';
+import { decoderName } from '@/lib/decoderName';
 import { subscribeRotorHeading, pokeRotorHeading } from '@/lib/rotorHeading';
 import { writeUiPref } from '@/lib/uiPref';
 import { formatDateTimeUTC } from '@/lib/dateFormat';
@@ -2406,6 +2407,17 @@ export default function App() {
   // the watchlist panel: a call can be added from the cluster or the
   // DXpeditions tab, and the old inline message lived on a page nobody was
   // looking at.
+  // The watch list as patterns, for the decodes badge. Loaded once and kept in
+  // step with the same event the notice below listens to — a call added from
+  // the cluster has to light up in the decodes list too.
+  const [watchPatterns, setWatchPatterns] = useState<string[]>([]);
+  const loadWatchPatterns = useCallback(() => {
+    WatchlistEntries()
+      .then((es: any[]) => setWatchPatterns((es ?? []).map((e: any) => String(e?.callsign ?? '')).filter(Boolean)))
+      .catch(() => {});
+  }, []);
+  useEffect(() => { loadWatchPatterns(); }, [loadWatchPatterns]);
+  useEffect(() => EventsOn('watchlist:changed', () => loadWatchPatterns()), [loadWatchPatterns]);
   const [wlNotice, setWlNotice] = useState<{ call: string; added: boolean } | null>(null);
   const wlNoticeTimer = useRef<number | undefined>(undefined);
   useEffect(() => EventsOn('watchlist:changed', (e: any) => {
@@ -2597,6 +2609,9 @@ export default function App() {
   // Staged like the cluster's, so a period arriving as one burst of fifty
   // packets costs one status lookup and one render, not fifty of each.
   const pendingDecodesRef = useRef<DecodeRow[]>([]);
+  // The band each receiver was last decoding on. A band change empties that
+  // receiver's list — see the flush below.
+  const decoderBandRef = useRef<Map<string, string>>(new Map());
   const pendingDecodeTimer = useRef<number | undefined>(undefined);
 
   // Rotor quick-turn buttons (Settings → Rotator). Same reload trigger as the
@@ -3718,9 +3733,42 @@ export default function App() {
           });
         }
       } catch { /* status unresolved — the decode still shows, just unflagged */ }
+      // A BAND CHANGE empties that receiver's list.
+      //
+      // What is on 20 m says nothing about 40 m, and half a screen of stations
+      // that are no longer reachable is worse than an empty one: the period
+      // headings still march on, the rows still carry status badges, and the
+      // operator reads a band they have left. Per receiver — in a split view
+      // the other one has not moved — and only when the new band is known.
+      const moved = new Map<string, string>();
+      for (const d of batch) {
+        const inst = d.instance ?? '';
+        const band = (d.band ?? '').toLowerCase();
+        if (!band) continue;
+        const was = decoderBandRef.current.get(inst);
+        decoderBandRef.current.set(inst, band);
+        if (was && was !== band) moved.set(inst, band);
+      }
+      if (moved.size > 0) {
+        for (const [inst, band] of moved) {
+          LogUIError('decodes', `${decoderName(inst) || 'decoder'} moved to ${band.toUpperCase()} — its earlier decodes cleared`, '');
+        }
+        setTxMsgs((arr) => arr.filter((m) => !moved.has(m.instance ?? '')));
+      }
       setDecodes((arr) => {
         const cutoff = Date.now() - DECODE_KEEP_MS;
-        const next = [...arr, ...batch].filter((d) => Date.parse(d.at) >= cutoff);
+        // Rows from a receiver that has just changed band go with it — the
+        // batch itself is already on the new band.
+        const kept = moved.size === 0 ? arr : arr.filter((d) => !moved.has(d.instance ?? ''));
+        // The batch can straddle the change — a 300 ms flush can hold the last
+        // decodes of the old band and the first of the new. Only the new band
+        // survives for a receiver that moved.
+        const fresh = moved.size === 0 ? batch
+          : batch.filter((d) => {
+            const b2 = moved.get(d.instance ?? '');
+            return !b2 || (d.band ?? '').toLowerCase() === b2;
+          });
+        const next = [...kept, ...fresh].filter((d) => Date.parse(d.at) >= cutoff);
         return next;
       });
     };
@@ -6385,15 +6433,16 @@ export default function App() {
       // An empty instance lets the backend fall back to whichever application
       // last reported its status — the normal single-receiver case.
       onHalt={(instance) => {
-        // Halt means stop, including whatever auto-call had started — and it
-        // clears the engine's state, so a target it had given up on is not
-        // still sitting there when the operator switches it back on.
-        ResetAutoCall().catch(() => {});
+        // Halt is a verdict on the station being called: it is set aside for
+        // the session rather than released, or the next period would call it
+        // straight back — which is exactly what the operator just stopped.
+        HaltAutoCall().catch(() => {});
         HaltDecodeTx(instance, false).catch((e: any) => setError(String(e?.message ?? e)));
       }}
       autoCallOn={!!autoCallStatus?.enabled}
       onToggleAutoCall={toggleAutoCall}
       autoCall={autoCallStatus}
+      watchlist={watchPatterns}
       autoCallOnly={autoCallStatus?.only ?? ''}
       onSetAutoCallOnly={(list) => {
         setAutoCallStatus((st: any) => ({ ...st, only: list.toUpperCase() }));