Implement comprehensive notification system for LittleShop

- Add admin PWA push notifications for order management
- Integrate TeleBot customer messaging service
- Add push notification endpoints and VAPID key support
- Implement order status notifications throughout workflow
- Add notification UI components in admin panel
- Create TeleBotMessagingService for customer updates
- Add WebPush configuration to appsettings
- Fix compilation issues (BotStatus, BotContacts DbSet)
- Add comprehensive testing documentation

Features:
- Real-time admin notifications for new orders and status changes
- Customer order progress updates via TeleBot
- Graceful failure handling for notification services
- Test endpoints for notification system validation

🤖 Generated with Claude Code
Co-Authored-By: Claude <noreply@anthropic.com>

LittleShop/appsettings.Production.json

@@ -28,6 +28,10 @@
     "ForwardedForHeaderName": "X-Forwarded-For",
     "ForwardedHostHeaderName": "X-Forwarded-Host"
   },
+  "TeleBot": {
+    "ApiUrl": "${TELEBOT_API_URL}",
+    "ApiKey": "${TELEBOT_API_KEY}"
+  },
   "Serilog": {
     "Using": [ "Serilog.Sinks.Console", "Serilog.Sinks.File" ],
     "MinimumLevel": "Information",