fix: unify wheel Stars payment across desktop and mobile

- Use Telegram Stars invoice on all platforms instead of balance
  payment on desktop
- Show star cost in toggle and subtitle everywhere
- Show popup/toast when Stars are not enabled and user tries to spin
- Remove platform-specific payment type auto-select logic
- Add starsNotAvailable translation key (ru, en, zh, fa)

src/locales/en.json

@@ -713,6 +713,7 @@
     "starsPaymentSuccessCheckHistory": "Payment successful! Check history or Telegram for the result.",
     "starsPaymentFailed": "Payment failed. Please try again.",
     "starsPaymentRedirected": "Telegram will open for payment. Refresh the page after payment.",
+    "starsNotAvailable": "Star payments are currently unavailable. Contact support.",
     "youWon": "You won",
     "noPrize": "No luck this time...",
     "noHistory": "No spin history yet",