feat: add purchases list with pagination to landing stats page

Add card-based purchase list below charts with:
- Status filter dropdown (all/pending/paid/delivered/etc)
- Paginated card list with contact, gift recipient, tariff, price
- Status badges, responsive mobile/desktop layout
- Translations for ru/en

src/api/landings.ts

@@ -305,6 +305,41 @@ export interface LandingStatsResponse {
   tariff_stats: LandingTariffStat[];
 }
 
+// ============================================================
+// Admin purchase list types
+// ============================================================
+
+export type PurchaseItemStatus =
+  | 'pending'
+  | 'paid'
+  | 'delivered'
+  | 'pending_activation'
+  | 'failed'
+  | 'expired';
+
+export interface LandingPurchaseItem {
+  id: number;
+  token: string;
+  contact_type: 'email' | 'telegram';
+  contact_value: string;
+  is_gift: boolean;
+  gift_recipient_type: 'email' | 'telegram' | null;
+  gift_recipient_value: string | null;
+  tariff_name: string;
+  period_days: number;
+  amount_kopeks: number;
+  currency: string;
+  payment_method: string;
+  status: PurchaseItemStatus;
+  created_at: string;
+  paid_at: string | null;
+}
+
+export interface LandingPurchaseListResponse {
+  items: LandingPurchaseItem[];
+  total: number;
+}
+
 // ============================================================
 // Admin API
 // ============================================================
@@ -348,4 +383,16 @@ export const adminLandingsApi = {
     const response = await apiClient.get(`/cabinet/admin/landings/${id}/stats`);
     return response.data;
   },
+
+  getPurchases: async (
+    id: number,
+    offset: number,
+    limit: number,
+    status?: PurchaseItemStatus,
+  ): Promise<LandingPurchaseListResponse> => {
+    const params: Record<string, string | number> = { offset, limit };
+    if (status) params.status = status;
+    const response = await apiClient.get(`/cabinet/admin/landings/${id}/purchases`, { params });
+    return response.data;
+  },
 };