fix(ui): correct the VK-iOS purchase block + add an iOS store note

The VK-iOS detection used platformSubtype(), which is server-derived for VK and
so never reported iOS on the client — the pack CTA stayed active and a tap hit a
403 with a generic error. Read the device family from the signed vk_platform
launch param (normalizeSubtype(vkPlatform())) instead. Under the store header on
VK-iOS, add a note that purchases are prohibited by Apple policy, linking to the
web version (opened through VK's external-link route).

ui/src/lib/i18n/en.ts

@@ -244,6 +244,9 @@ export const en = {
   'wallet.buy': 'Buy',
   'wallet.offer': 'Public offer',
   'wallet.platformNoBuy': 'Purchases are not available on this platform',
+  'wallet.iosBlockedPre': 'Purchases on iOS are prohibited by Apple policy. Try the ',
+  'wallet.iosBlockedLink': 'other version',
+  'wallet.iosBlockedPost': ' of the game.',
   'wallet.gpStub': 'To buy chips, install the RuStore build.',
   'wallet.cur.RUB': '₽',
   'wallet.cur.VOTE': 'votes',

ui/src/lib/i18n/ru.ts

@@ -244,6 +244,9 @@ export const ru: Record<MessageKey, string> = {
   'wallet.buy': 'Купить',
   'wallet.offer': 'Публичная оферта',
   'wallet.platformNoBuy': 'На данной платформе покупки невозможны',
+  'wallet.iosBlockedPre': 'Покупки на iOS запрещены политикой Apple. Попробуйте воспользоваться ',
+  'wallet.iosBlockedLink': 'другой версией',
+  'wallet.iosBlockedPost': ' игры.',
   'wallet.gpStub': 'Чтобы покупать фишки, установите версию из RuStore.',
   'wallet.cur.RUB': '₽',
   'wallet.cur.VOTE': 'голосов',