Implement SignalR integration and refactor WeatherPage

Added SignalR for real-time progress updates during weather data fetch. Refactored WeatherPage to use a new reusable WeatherGrid component and SignalRHelper. Improved loading UI with a radial progress indicator.

Api/SignalR/SignalRSendService.cs

@@ -18,7 +18,7 @@ namespace Api.SignalR
                 logger.LogInformation("Background service sending message at: {Time}", DateTime.Now);
 
                 // Send a message to all connected clients.
-                await hubContext.Clients.User("user1234").SendAsync(
+                await hubContext.Clients.All.SendAsync(
                     "ReceiveMessage", // This is the client method name.
                     "Background Service", // Example sender.
                     $"Hello from the background task at {DateTime.Now:F}", // The message.