fix(labels): the manager's address, not the DX's — and one PDF, just opened

Three corrections from the first real session. Routed via a manager, the box
was prefilled with the DX's own address — the one thing that must not go on
that envelope. It now starts empty and the QRZ fetch fills in the MANAGER's;
switching the routing recomputes the box unless the operator has typed in it,
because a hand-checked address is not the app's to replace.

A fetch that came back with no street was overwriting a reviewed address with a
bare country — the cty.dat fallback dressed as an answer. It now refuses to
touch the box and says nothing was found. And the prefill no longer stacks the
same town three times (address + QTH + country all carrying it).

The output is ONE PDF for the whole session, each page at its own label size,
written to the temp dir and opened straight in the viewer — no save dialog: the
file is a print run, not a document to keep.

frontend/src/lib/i18n.tsx

@@ -149,6 +149,7 @@ const en: Dict = {
   'lpr.noAddrTpl': "No address label template — create one in the Label Designer first.",
   'lpr.pageCount': "{n} label(s) — one PDF page each",
   'lpr.savePdf': "Save PDF & open",
+  'lpr.openPdf': "Open the PDF ({n} labels)", 'lpr.mgrAddressPh': "Manager address — use Fetch (QRZ)",
   'lpr.markTitle': "Record in the log", 'lpr.markBtn': "Mark {n} QSO(s) sent",
   'lpr.markHint': "Sets QSL sent = Y with this date; via becomes B for bureau and D for direct or manager.",
   'lpr.markDone': "{n} QSO(s) updated.",
@@ -693,6 +694,7 @@ const fr: Dict = {
   'lpr.noAddrTpl': "Aucun modèle d'étiquette adresse — créez-en un dans le Créateur d'étiquettes.",
   'lpr.pageCount': "{n} étiquette(s) — une page PDF chacune",
   'lpr.savePdf': "Enregistrer le PDF et ouvrir",
+  'lpr.openPdf': "Ouvrir le PDF ({n} étiquettes)", 'lpr.mgrAddressPh': "Adresse du manager — utilisez Récupérer (QRZ)",
   'lpr.markTitle': "Enregistrer dans le log", 'lpr.markBtn': "Marquer {n} QSO envoyés",
   'lpr.markHint': "Passe QSL envoyée = Y à cette date ; le moyen devient B pour bureau et D pour direct ou manager.",
   'lpr.markDone': "{n} QSO mis à jour.",