Improve the user interface and add CSV export to the sales history

Implements UI enhancements with visible section frames and adds CSV export functionality to SalesHistory.tsx and index.css.

Replit-Commit-Author: Agent
Replit-Commit-Session-Id: dec54137-d5a2-4406-8ad4-5f2f9fb110bf
Replit-Commit-Screenshot-Url: https://storage.googleapis.com/screenshot-production-us-central1/0715008c-7244-40f4-befc-26c014852236/9ba8b033-161d-4888-81d6-a484ee533451.jpg

replit.md

@@ -220,6 +220,20 @@ Preferred communication style: Simple, everyday language.
 - ✅ Safety confirmation dialogs for manual purge operations
 - ✅ Real-time monitoring of data retention status with visual indicators
 
+### Modern UI Design & Advanced Search (January 10, 2025)
+- ✅ Complete UI redesign with modern, elegant design system
+- ✅ Enhanced visual borders and frames throughout the application for better visibility
+- ✅ Colored sections with animations and smooth transitions
+- ✅ Made "autorité de délivrance" field optional in new sale form as requested
+- ✅ Added comprehensive search module in sales history with multi-field filtering
+- ✅ Real-time search across names, sellers, articles, codes, payment methods, and birth places
+- ✅ Added CSV export functionality alongside existing PDF export
+- ✅ Visible section frames around each category in new sale form
+- ✅ Enhanced cards and containers with stronger visual borders
+- ✅ Improved responsive design for mobile and tablet devices
+- ✅ Modern search interface with clear result counting and active search indicators
+- ✅ Dual export options (PDF and CSV) for regulatory compliance reporting
+
 ### Docker Configuration & Cleanup (January 9, 2025)
 - ✅ Complete Docker setup optimized for external PostgreSQL database
 - ✅ Docker Compose configuration with RegisFlow application only