feat(pairing): auto-close the QR/link dialog once the device connects

The pairing session is single-use, so it leaving the pending list (polled
every 5s) means it was redeemed — close the dialog and toast success. Armed
only after the pairing has been seen in the pending list, so the stale list
at result-phase open can't blink the dialog shut; expired/cancelled sessions
close it silently. Pending-list polling now preserves the previous list on a
transient fetch failure instead of blanking it (which would also have faked
the redeem signal).

packages/ui/src/lib/i18n/messages/pl.settings.ts

@@ -1492,6 +1492,7 @@ export const settingsDict = {
   'settings.remoteInstances.clientAuth.addDevice.fallback.preferLocal': 'Preferuj bezpośrednie połączenie domowe, gdy dostępne',
   'settings.remoteInstances.clientAuth.addDevice.create': 'Utwórz kod QR',
   'settings.remoteInstances.clientAuth.addDevice.done': 'Gotowe',
+  'settings.remoteInstances.clientAuth.addDevice.connectedToast': 'Urządzenie połączone.',
   'settings.remoteInstances.clientAuth.pairingUrl': 'Link połączenia',
   'settings.remoteInstances.clientAuth.createdToken': 'Skopiuj ten token teraz. Ze względów bezpieczeństwa nie zostanie pokazany ponownie.',
   'settings.remoteInstances.clientAuth.state.loading': 'Ładowanie tokenów...',