feat(cabinet): legal footer on login + admin toggle

Adds a legal footer (Public Offer / Privacy / Recurring Payments) under the
login card, gated by CABINET_FOOTER_ENABLED (backend endpoint added in bot
PR #3011), plus an admin toggle in BrandingTab and ru/en/fa/zh i18n.

Footer-only subset of PR #464 — excludes the unrelated storePartnerClickId
helper and the version/CHANGELOG churn.

Co-authored-by: smediainfo <dev@matrixvpn.top>

src/components/LegalFooter.tsx

@@ -0,0 +1,46 @@
+import { Fragment } from 'react';
+import { useTranslation } from 'react-i18next';
+
+interface LegalLink {
+  href: string;
+  labelKey: string;
+  fallback: string;
+}
+
+const LINKS: LegalLink[] = [
+  { href: '/offer', labelKey: 'footer.offer', fallback: 'Публичная оферта' },
+  { href: '/privacy', labelKey: 'footer.privacy', fallback: 'Политика конфиденциальности' },
+  { href: '/recurrent-payments', labelKey: 'footer.recurrent', fallback: 'Рекуррентные платежи' },
+];
+
+interface LegalFooterProps {
+  className?: string;
+}
+
+export default function LegalFooter({ className = '' }: LegalFooterProps) {
+  const { t } = useTranslation();
+
+  return (
+    <footer
+      className={`flex flex-wrap items-center justify-center gap-x-2.5 gap-y-1 text-center text-[11px] leading-relaxed text-dark-500 ${className}`}
+    >
+      {LINKS.map((link, index) => (
+        <Fragment key={link.href}>
+          {index > 0 && (
+            <span className="text-dark-700" aria-hidden="true">
+              ·
+            </span>
+          )}
+          <a
+            href={link.href}
+            target="_blank"
+            rel="noopener noreferrer"
+            className="transition-colors hover:text-accent-400"
+          >
+            {t(link.labelKey, link.fallback)}
+          </a>
+        </Fragment>
+      ))}
+    </footer>
+  );
+}

src/components/admin/BrandingTab.tsx

@@ -40,6 +40,11 @@ export function BrandingTab({ accentColor = '#3b82f6' }: BrandingTabProps) {
     queryFn: brandingApi.getGiftEnabled,
   });
 
+  const { data: footerEnabled } = useQuery({
+    queryKey: ['footer-enabled'],
+    queryFn: brandingApi.getFooterEnabled,
+  });
+
   // Mutations
   const updateBrandingMutation = useMutation({
     mutationFn: brandingApi.updateName,
@@ -88,6 +93,13 @@ export function BrandingTab({ accentColor = '#3b82f6' }: BrandingTabProps) {
     },
   });
 
+  const updateFooterMutation = useMutation({
+    mutationFn: (enabled: boolean) => brandingApi.updateFooterEnabled(enabled),
+    onSuccess: () => {
+      queryClient.invalidateQueries({ queryKey: ['footer-enabled'] });
+    },
+  });
+
   const handleLogoUpload = (e: React.ChangeEvent<HTMLInputElement>) => {
     const file = e.target.files?.[0];
     if (file) {
@@ -250,6 +262,25 @@ export function BrandingTab({ accentColor = '#3b82f6' }: BrandingTabProps) {
               disabled={updateGiftMutation.isPending}
             />
           </div>
+
+          <div className="flex items-center justify-between rounded-xl bg-dark-700/30 p-4">
+            <div>
+              <span className="font-medium text-dark-100">
+                {t('admin.settings.legalFooter', 'Юридический футер')}
+              </span>
+              <p className="text-sm text-dark-400">
+                {t(
+                  'admin.settings.legalFooterDesc',
+                  'Ссылки на оферту/политику/рекурренты внизу страницы входа',
+                )}
+              </p>
+            </div>
+            <Toggle
+              checked={footerEnabled ?? true}
+              onChange={() => updateFooterMutation.mutate(!(footerEnabled ?? true))}
+              disabled={updateFooterMutation.isPending}
+            />
+          </div>
         </div>
       </div>
     </div>