feat: публичные лендинг-страницы для быстрой покупки VPN-подписок

- QuickPurchase: публичная страница покупки с выбором тарифа/периода/оплаты
- PurchaseSuccess: статус покупки с поллингом и копированием ссылки
- AdminLandings: управление лендингами (создание, сортировка, удаление)
- AdminLandingEditor: полнофункциональный редактор лендинга
- API-клиент landings.ts для всех эндпоинтов
- Роутинг /buy/:slug и /buy/success/:token
- Локализация ru/en/zh/fa для всех текстов лендинга
- Санитизация HTML/CSS, rate limit защита, DOMPurify

src/api/client.ts

@@ -77,6 +77,7 @@ const AUTH_ENDPOINTS = [
   '/cabinet/auth/oauth/',
   '/cabinet/auth/merge/',
   '/cabinet/auth/account/link/server-complete',
+  '/cabinet/landing/',
 ];
 
 function isAuthEndpoint(url: string | undefined): boolean {

src/api/landings.ts

@@ -0,0 +1,199 @@
+import apiClient from './client';
+
+// ============================================================
+// Public types
+// ============================================================
+
+export interface LandingFeature {
+  icon: string;
+  title: string;
+  description: string;
+}
+
+export interface LandingTariffPeriod {
+  days: number;
+  label: string;
+  price_kopeks: number;
+  price_label: string;
+}
+
+export interface LandingTariff {
+  id: number;
+  name: string;
+  description: string | null;
+  traffic_limit_gb: number;
+  device_limit: number;
+  tier_level: number;
+  periods: LandingTariffPeriod[];
+}
+
+export interface LandingPaymentMethod {
+  method_id: string;
+  display_name: string;
+  description: string;
+  icon_url: string;
+  sort_order: number;
+}
+
+export interface LandingConfig {
+  slug: string;
+  title: string;
+  subtitle: string | null;
+  features: LandingFeature[];
+  footer_text: string | null;
+  tariffs: LandingTariff[];
+  payment_methods: LandingPaymentMethod[];
+  gift_enabled: boolean;
+  custom_css: string | null;
+  meta_title: string | null;
+  meta_description: string | null;
+}
+
+export interface PurchaseRequest {
+  tariff_id: number;
+  period_days: number;
+  contact_type: 'email' | 'telegram';
+  contact_value: string;
+  payment_method: string;
+  is_gift: boolean;
+  gift_recipient_type?: 'email' | 'telegram';
+  gift_recipient_value?: string;
+  gift_message?: string;
+}
+
+export interface PurchaseResponse {
+  purchase_token: string;
+  payment_url: string;
+}
+
+export interface PurchaseStatus {
+  status: 'pending' | 'paid' | 'delivered' | 'failed' | 'expired';
+  subscription_url: string | null;
+  subscription_crypto_link: string | null;
+  is_gift: boolean;
+  contact_value: string | null;
+  period_days: number | null;
+  tariff_name: string | null;
+}
+
+// ============================================================
+// Admin types
+// ============================================================
+
+export interface LandingListItem {
+  id: number;
+  slug: string;
+  title: string;
+  is_active: boolean;
+  display_order: number;
+  gift_enabled: boolean;
+  tariff_count: number;
+  method_count: number;
+  purchase_stats: {
+    total: number;
+    paid: number;
+    pending: number;
+    failed: number;
+  };
+  created_at: string | null;
+  updated_at: string | null;
+}
+
+export interface LandingDetail {
+  id: number;
+  slug: string;
+  title: string;
+  subtitle: string | null;
+  is_active: boolean;
+  features: LandingFeature[];
+  footer_text: string | null;
+  allowed_tariff_ids: number[];
+  allowed_periods: Record<string, number[]>;
+  payment_methods: LandingPaymentMethod[];
+  gift_enabled: boolean;
+  custom_css: string | null;
+  meta_title: string | null;
+  meta_description: string | null;
+  display_order: number;
+  created_at: string | null;
+  updated_at: string | null;
+}
+
+export interface LandingCreateRequest {
+  slug: string;
+  title: string;
+  subtitle?: string;
+  is_active?: boolean;
+  features?: LandingFeature[];
+  footer_text?: string;
+  allowed_tariff_ids?: number[];
+  allowed_periods?: Record<string, number[]>;
+  payment_methods?: LandingPaymentMethod[];
+  gift_enabled?: boolean;
+  custom_css?: string;
+  meta_title?: string;
+  meta_description?: string;
+}
+
+export type LandingUpdateRequest = Partial<LandingCreateRequest>;
+
+// ============================================================
+// Public API
+// ============================================================
+
+export const landingApi = {
+  getConfig: async (slug: string): Promise<LandingConfig> => {
+    const response = await apiClient.get(`/cabinet/landing/${slug}`);
+    return response.data;
+  },
+
+  createPurchase: async (slug: string, data: PurchaseRequest): Promise<PurchaseResponse> => {
+    const response = await apiClient.post(`/cabinet/landing/${slug}/purchase`, data);
+    return response.data;
+  },
+
+  getPurchaseStatus: async (token: string): Promise<PurchaseStatus> => {
+    const response = await apiClient.get(`/cabinet/landing/purchase/${token}`);
+    return response.data;
+  },
+};
+
+// ============================================================
+// Admin API
+// ============================================================
+
+export const adminLandingsApi = {
+  list: async (): Promise<LandingListItem[]> => {
+    const response = await apiClient.get('/cabinet/admin/landings');
+    return response.data;
+  },
+
+  get: async (id: number): Promise<LandingDetail> => {
+    const response = await apiClient.get(`/cabinet/admin/landings/${id}`);
+    return response.data;
+  },
+
+  create: async (data: LandingCreateRequest): Promise<LandingDetail> => {
+    const response = await apiClient.post('/cabinet/admin/landings', data);
+    return response.data;
+  },
+
+  update: async (id: number, data: LandingUpdateRequest): Promise<LandingDetail> => {
+    const response = await apiClient.put(`/cabinet/admin/landings/${id}`, data);
+    return response.data;
+  },
+
+  delete: async (id: number): Promise<{ message: string }> => {
+    const response = await apiClient.delete(`/cabinet/admin/landings/${id}`);
+    return response.data;
+  },
+
+  toggle: async (id: number): Promise<{ id: number; is_active: boolean; message: string }> => {
+    const response = await apiClient.post(`/cabinet/admin/landings/${id}/toggle`);
+    return response.data;
+  },
+
+  reorder: async (landingIds: number[]): Promise<void> => {
+    await apiClient.put('/cabinet/admin/landings/order', { landing_ids: landingIds });
+  },
+};