feat(hamqth): QSO upload to the HamQTH logbook — the 8th external service

qso_realtime.php with the account's callbook credentials (which the
external-services config falls back to when its own are blank), one ADIF
record per QSO, prg=OpsLog. HTTP status IS the answer: 200 saved, 400
rejected (a duplicate counts as delivered, like HRDLog's insert 0), 403
credentials. Sent-state lives in APP_OPSLOG_HAMQTH_SENT extras like
HAMLOG.online — ADIF names no HamQTH field. Auto-upload on log, on-close
batch, right-click Send to, QSL Manager backlog, and a Test button that
authenticates against the callbook login, which cannot touch the log.

Fixes a real mis-route on the way: manual 'Send to HAMLOG.online' had no
branch in runManualUpload and fell through to QRZ.com — the selection was
uploaded to the wrong service with the QRZ key. Both extras-stamped
services now have their own branch.

frontend/wailsjs/go/main/App.js

@@ -2606,6 +2606,10 @@ export function TestHRDLogUpload() {
   return window['go']['main']['App']['TestHRDLogUpload']();
 }
 
+export function TestHamQTHUpload() {
+  return window['go']['main']['App']['TestHamQTHUpload']();
+}
+
 export function TestLoTWUpload() {
   return window['go']['main']['App']['TestLoTWUpload']();
 }