feat: add gift subscription toggle to admin branding settings

Add CABINET_GIFT_ENABLED toggle in Admin Settings > Branding > Interface Options,
alongside existing fullscreen and email auth toggles. Includes updateGiftEnabled
API method and i18n keys for all 4 locales (ru/en/zh/fa).

src/api/branding.ts

@@ -265,6 +265,14 @@ export const brandingApi = {
     }
   },
 
+  // Update gift enabled (admin only)
+  updateGiftEnabled: async (enabled: boolean): Promise<GiftEnabled> => {
+    const response = await apiClient.patch<GiftEnabled>('/cabinet/branding/gift-enabled', {
+      enabled,
+    });
+    return response.data;
+  },
+
   // Get analytics counters (public, no auth required)
   getAnalyticsCounters: async (): Promise<AnalyticsCounters> => {
     try {

src/components/admin/BrandingTab.tsx

@@ -35,6 +35,11 @@ export function BrandingTab({ accentColor = '#3b82f6' }: BrandingTabProps) {
     queryFn: brandingApi.getEmailAuthEnabled,
   });
 
+  const { data: giftSettings } = useQuery({
+    queryKey: ['gift-enabled'],
+    queryFn: brandingApi.getGiftEnabled,
+  });
+
   // Mutations
   const updateBrandingMutation = useMutation({
     mutationFn: brandingApi.updateName,
@@ -76,6 +81,13 @@ export function BrandingTab({ accentColor = '#3b82f6' }: BrandingTabProps) {
     },
   });
 
+  const updateGiftMutation = useMutation({
+    mutationFn: (enabled: boolean) => brandingApi.updateGiftEnabled(enabled),
+    onSuccess: () => {
+      queryClient.invalidateQueries({ queryKey: ['gift-enabled'] });
+    },
+  });
+
   const handleLogoUpload = (e: React.ChangeEvent<HTMLInputElement>) => {
     const file = e.target.files?.[0];
     if (file) {
@@ -225,6 +237,18 @@ export function BrandingTab({ accentColor = '#3b82f6' }: BrandingTabProps) {
               disabled={updateEmailAuthMutation.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.giftEnabled')}</span>
+              <p className="text-sm text-dark-400">{t('admin.settings.giftEnabledDesc')}</p>
+            </div>
+            <Toggle
+              checked={giftSettings?.enabled ?? false}
+              onChange={() => updateGiftMutation.mutate(!(giftSettings?.enabled ?? false))}
+              disabled={updateGiftMutation.isPending}
+            />
+          </div>
         </div>
       </div>
     </div>

src/locales/en.json

@@ -1696,6 +1696,8 @@
       "darkTheme": "Dark theme",
       "emailAuth": "Email auth",
       "emailAuthDesc": "Allow login via email",
+      "giftEnabled": "Gift subscription",
+      "giftEnabledDesc": "Allow users to gift a subscription to another user",
       "favoritesEmpty": "No favorites yet",
       "favoritesHint": "Star settings to add them here",
       "interfaceOptions": "Interface options",

src/locales/fa.json

@@ -1367,6 +1367,8 @@
       "darkTheme": "پوسته تیره",
       "emailAuth": "احراز هویت ایمیل",
       "emailAuthDesc": "اجازه ورود با ایمیل",
+      "giftEnabled": "اشتراک هدیه",
+      "giftEnabledDesc": "امکان ارسال اشتراک به عنوان هدیه به کاربر دیگر",
       "favoritesEmpty": "هنوز علاقه‌مندی ندارید",
       "favoritesHint": "ستاره بزنید تا تنظیمات اینجا اضافه شوند",
       "interfaceOptions": "گزینه‌های رابط کاربری",

src/locales/ru.json

@@ -1706,6 +1706,8 @@
       "autoFullscreenDesc": "В Telegram WebApp",
       "emailAuth": "Email авторизация",
       "emailAuthDesc": "Регистрация и вход через email",
+      "giftEnabled": "Подписка в подарок",
+      "giftEnabledDesc": "Возможность отправить подписку в подарок другому пользователю",
       "availableThemes": "Доступные темы",
       "darkTheme": "Тёмная",
       "lightTheme": "Светлая",

src/locales/zh.json

@@ -1405,6 +1405,8 @@
       "darkTheme": "暗色主题",
       "emailAuth": "邮箱认证",
       "emailAuthDesc": "允许通过邮箱登录",
+      "giftEnabled": "赠送订阅",
+      "giftEnabledDesc": "允许用户将订阅作为礼物赠送给其他用户",
       "favoritesEmpty": "暂无收藏",
       "favoritesHint": "点击星标将设置添加到这里",
       "interfaceOptions": "界面选项",