feat: implement analytics dashboard layout (task 10)

- Add analytics types (AnalyticsSummary, DateRange)
- Create analyticsService for API calls and CSV export
- Implement DateRangeSelector component with presets
- Create StatCard component for summary statistics
- Build responsive AnalyticsPage with:
  - Summary statistics cards (reports, events, users, litter collected)
  - Date range filtering with presets
  - CSV export functionality
  - Loading and error states
  - Responsive grid layout

Requirements: 5.1, 5.5

src/services/analyticsService.ts

@@ -0,0 +1,51 @@
+// Analytics service for API interactions
+import { apiClient } from './api';
+import type { AnalyticsSummary } from '@/types';
+
+class AnalyticsService {
+  /**
+   * Get summary statistics for the analytics dashboard
+   */
+  async getSummary(dateRange?: { start: string; end: string }): Promise<AnalyticsSummary> {
+    const params = new URLSearchParams();
+    
+    if (dateRange) {
+      params.append('startDate', dateRange.start);
+      params.append('endDate', dateRange.end);
+    }
+
+    const queryString = params.toString();
+    return apiClient.get<AnalyticsSummary>(`/analytics/summary${queryString ? `?${queryString}` : ''}`);
+  }
+
+  /**
+   * Export analytics data to CSV
+   */
+  async exportToCSV(dateRange?: { start: string; end: string }): Promise<Blob> {
+    const params = new URLSearchParams();
+    
+    if (dateRange) {
+      params.append('startDate', dateRange.start);
+      params.append('endDate', dateRange.end);
+    }
+
+    const queryString = params.toString();
+    const response = await fetch(
+      `${import.meta.env.VITE_API_BASE_URL || 'http://localhost:3000/api'}/analytics/export${queryString ? `?${queryString}` : ''}`,
+      {
+        method: 'GET',
+        headers: {
+          'Accept': 'text/csv',
+        },
+      }
+    );
+
+    if (!response.ok) {
+      throw new Error('Failed to export data');
+    }
+
+    return response.blob();
+  }
+}
+
+export const analyticsService = new AnalyticsService();