feat: add recharts analytics to admin campaign stats page

- Move shared chart components (DailyChart, PeriodComparison, StatCard) to src/components/stats/ with configurable label props
- Create shared types for chart data decoupled from partner API
- Add campaign chart data API client with deposits/spending split
- Enhance AdminCampaignStats with daily trends chart, period comparison, top registrations, and deposit/spending stat cards
- Add useChartColors hook with SSR guard and theme-aware CSS variable parsing
- Add cross-platform clipboard utility with execCommand fallback for Telegram WebView
- Add i18n keys for chart analytics across all 4 locales (en, ru, zh, fa)
- Responsive fixes: truncation for long names/values, responsive text sizing, touch-friendly copy buttons

src/api/campaigns.ts

@@ -149,6 +149,49 @@ export interface CampaignsOverview {
   total_tariff_issued: number;
 }
 
+export interface AdminDailyStatItem {
+  date: string;
+  referrals_count: number;
+  earnings_kopeks: number;
+}
+
+export interface AdminPeriodStats {
+  days: number;
+  referrals_count: number;
+  earnings_kopeks: number;
+}
+
+export interface AdminPeriodChange {
+  absolute: number;
+  percent: number;
+  trend: 'up' | 'down' | 'stable';
+}
+
+export interface AdminPeriodComparison {
+  current: AdminPeriodStats;
+  previous: AdminPeriodStats;
+  referrals_change: AdminPeriodChange;
+  earnings_change: AdminPeriodChange;
+}
+
+export interface AdminTopRegistrationItem {
+  id: number;
+  full_name: string;
+  created_at: string;
+  has_paid: boolean;
+  is_active: boolean;
+  total_earnings_kopeks: number;
+}
+
+export interface AdminCampaignChartData {
+  campaign_id: number;
+  total_deposits_kopeks: number;
+  total_spending_kopeks: number;
+  daily_stats: AdminDailyStatItem[];
+  period_comparison: AdminPeriodComparison;
+  top_registrations: AdminTopRegistrationItem[];
+}
+
 export interface ServerSquadInfo {
   id: number;
   squad_uuid: string;
@@ -258,4 +301,10 @@ export const campaignsApi = {
     const response = await apiClient.get('/cabinet/admin/campaigns/available-partners');
     return response.data;
   },
+
+  // Get campaign chart data for analytics
+  getChartData: async (campaignId: number): Promise<AdminCampaignChartData> => {
+    const response = await apiClient.get(`/cabinet/admin/campaigns/${campaignId}/chart-data`);
+    return response.data;
+  },
 };