feat: gift subscription redesign — code-only purchase + 3-tab UI

- Remove recipient input from buy flow (code-only gifts)
- 3-tab UI: Buy, Activate, My Gifts with animations
- After purchase, switch to My Gifts tab to show gift code
- Gift code display with copy/share buttons
- Activate tab: enter gift code to activate subscription
- My Gifts tab: sent/received gifts with status badges
- Fix: use navigator.language instead of hardcoded ru-RU for dates
- Fix: spread array before sort to prevent React Query cache mutation
- Fix: ARIA tab linkage with proper id/aria-labelledby
- Fix: guard VITE_BOT_USERNAME against undefined in share URLs
- Fix: wrap clipboard/share fallbacks in try/catch
- Add error state to MyGiftsTabContent

src/locales/en.json

@@ -4201,6 +4201,41 @@
     },
     "warning": {
       "telegram_unresolvable": "Could not verify this Telegram username. The recipient may not receive a notification about the gift."
-    }
+    },
+    "pageTitle": "Gifts",
+    "tabBuy": "Buy",
+    "tabActivate": "Activate",
+    "tabMyGifts": "My Gifts",
+    "selectTariff": "SELECT TARIFF",
+    "selectPeriod": "SUBSCRIPTION PERIOD",
+    "deviceCount": "{{count}} device",
+    "deviceCount_other": "{{count}} devices",
+    "activateTitle": "Enter gift code",
+    "activateDescription": "Enter the gift code you received from a friend",
+    "activateCodePlaceholder": "GIFT-XXXXXXXXXXXX",
+    "activateButton": "Activate gift",
+    "activating": "Activating...",
+    "activateSuccess": "Gift activated!",
+    "activateSuccessDesc": "{{tariff}} — {{days}} days added to your subscription",
+    "activateError": "Failed to activate gift",
+    "myGiftsEmpty": "No gifts yet",
+    "myGiftsEmptyDesc": "Buy a gift for a friend or activate a received code",
+    "sentGiftsTitle": "Sent",
+    "receivedGiftsTitle": "Received",
+    "statusAvailable": "AVAILABLE",
+    "statusActivated": "ACTIVATED",
+    "statusPending": "PENDING",
+    "statusDelivered": "DELIVERED",
+    "statusFailed": "FAILED",
+    "statusExpired": "EXPIRED",
+    "statusPendingActivation": "PENDING ACTIVATION",
+    "copyCode": "COPY",
+    "codeCopied": "Code copied!",
+    "shareGift": "SHARE",
+    "shareText": "I have a gift for you! Activate it here:",
+    "activatedBy": "Activated by {{username}}",
+    "sentTo": "Sent to {{recipient}}",
+    "daysShort": "days",
+    "devicesShort": "dev."
   }
 }