fix(cabinet): recover "Сервис недоступен" false-positive + top-up fixes

- health probe: tolerant timeout (12s) + retry before flagging the backend down. A
  hardcoded 5s probe racing auth bootstrap falsely showed ServiceUnavailableScreen on
  slow devices / cold mobile connections while the 30s API requests would have
  succeeded ("works on one device, not another on the same Wi-Fi"). The recovery poll
  self-reschedules with the tolerant timeout so slow devices auto-recover.
- TopUpAmount: fetch payment methods with a real query (fixes the infinite spinner on a
  cold cache / browser-back) and use canonical RUB for quick-amount chips so FX rounding
  can't reject a min-amount selection in non-RUB locales.
- settings UI: render secret values as a masked password input (pairs with the backend
  secret masking); leaving the field empty keeps the stored secret.
- deps: npm audit fix (18 -> 5 advisories).

Also bundles in-progress settings env-lock UI work.

src/components/admin/QuickToggles.tsx

@@ -13,7 +13,9 @@ interface QuickTogglesProps {
 export function QuickToggles({ settings, onUpdate, disabled, className }: QuickTogglesProps) {
   const { t } = useTranslation();
 
-  const booleanSettings = settings.filter((s) => s.type === 'bool' && !s.read_only);
+  const booleanSettings = settings.filter(
+    (s) => s.type === 'bool' && !s.read_only && !s.env_locked,
+  );
 
   if (booleanSettings.length === 0) {
     return null;