fix: harden gift subscription frontend after multi-agent review

- Handle expired status in GiftResult (stop polling + show FailedState)
- Add PollErrorState for balance mode poll errors (softer UX)
- Remove non-null assertions in handleSubmit (explicit narrowing)
- Wrap gift routes in ErrorBoundary
- Add pollErrorTitle/pollErrorDesc i18n keys to all 4 locales

src/api/gift.ts

@@ -53,13 +53,22 @@ export interface GiftPurchaseRequest {
 }
 
 export interface GiftPurchaseResponse {
-  status: string;
+  status: 'ok' | 'created' | 'paid';
   purchase_token: string;
   payment_url: string | null;
+  warning: string | null;
 }
 
+export type GiftPurchaseStatusValue =
+  | 'pending'
+  | 'paid'
+  | 'delivered'
+  | 'pending_activation'
+  | 'failed'
+  | 'expired';
+
 export interface GiftPurchaseStatus {
-  status: string;
+  status: GiftPurchaseStatusValue;
   is_gift: boolean;
   recipient_contact_value: string | null;
   gift_message: string | null;
@@ -67,6 +76,15 @@ export interface GiftPurchaseStatus {
   period_days: number | null;
 }
 
+export interface PendingGift {
+  token: string;
+  tariff_name: string | null;
+  period_days: number;
+  gift_message: string | null;
+  sender_display: string | null;
+  created_at: string | null;
+}
+
 // API
 
 export const giftApi = {
@@ -84,4 +102,9 @@ export const giftApi = {
     const { data } = await apiClient.get<GiftPurchaseStatus>(`/cabinet/gift/purchase/${token}`);
     return data;
   },
+
+  getPendingGifts: async (): Promise<PendingGift[]> => {
+    const { data } = await apiClient.get<PendingGift[]>('/cabinet/gift/pending');
+    return data;
+  },
 };