feat(qso-edit): QRZ button to open the station's qrz.com profile

Mirrors the main entry form: a QRZ ↗ button by the callsign in the QSO edit
modal opens https://www.qrz.com/db/<call> via OpenExternalURL.

frontend/src/components/QSOEditModal.tsx

@@ -1,6 +1,6 @@
 import { useEffect, useMemo, useRef, useState } from 'react';
 import { Trash2, Search, Loader2, CalendarDays } from 'lucide-react';
-import { LookupCallsign, LookupCallsignFresh, DXCCForCountry, GetAwardDefs, ComputeQSOAwardRefs, GetListsSettings } from '../../wailsjs/go/main/App';
+import { LookupCallsign, LookupCallsignFresh, DXCCForCountry, GetAwardDefs, ComputeQSOAwardRefs, GetListsSettings, OpenExternalURL } from '../../wailsjs/go/main/App';
 import { rstOptions, type RSTLists } from '@/lib/rst';
 import { AwardRefSelector } from '@/components/AwardRefSelector';
 import { AdifExtrasEditor } from '@/components/AdifExtrasEditor';
@@ -466,7 +466,22 @@ export function QSOEditModal({ qso, onSave, onDelete, onClose, countries = [], b
               {/* Top: Callsign + RST + Fetch */}
               <div className="flex items-end gap-2 mb-3">
                 <div className="flex flex-col flex-1 min-w-0">
-                  <Label>{t('qedit.callsign')}</Label>
+                  <div className="flex items-center">
+                    <Label>{t('qedit.callsign')}</Label>
+                    {(draft.callsign ?? '').trim() && (
+                      <button
+                        type="button"
+                        title={t('qrz.openTitle', { call: (draft.callsign ?? '').trim().toUpperCase() })}
+                        onClick={() => {
+                          const c = (draft.callsign ?? '').trim().toUpperCase().split('/').map(encodeURIComponent).join('/');
+                          if (c) OpenExternalURL(`https://www.qrz.com/db/${c}`).catch((e: any) => setLocalErr(String(e?.message ?? e)));
+                        }}
+                        className="ml-auto shrink-0 inline-flex items-center gap-0.5 text-[9px] font-semibold normal-case tracking-wider text-primary hover:underline"
+                      >
+                        QRZ ↗
+                      </button>
+                    )}
+                  </div>
                   <Input className="font-mono text-lg font-bold tracking-wider uppercase h-10"
                     value={draft.callsign ?? ''} onChange={(e) => set('callsign', e.target.value)} />
                 </div>