fix: block wheel spin without active subscription

- Add has_subscription to WheelConfig type
- Disable spin button when user has no subscription
- Add noSubscription guard in handleUnifiedSpin handler
- Show warning banner directing user to activate subscription
- Prevent banner stacking (noSubscription takes priority over daily limit)
- Add noSubscription i18n keys for ru, en, zh, fa

src/locales/zh.json

@@ -698,7 +698,8 @@
       "cannotSpin": "当前无法抽奖",
       "insufficientBalance": "余额不足",
       "topUpRequired": "请充值以支付抽奖费用",
-      "starsNotAvailable": "Stars支付不可用。请通过Telegram打开应用。"
+      "starsNotAvailable": "Stars支付不可用。请通过Telegram打开应用。",
+      "noSubscription": "需要有效订阅才能转动轮盘。请先激活订阅。"
     },
     "payWithStars": "支付 {stars} Stars",
     "processingPayment": "处理中...",