feature: Server error provider added, client notification service added

WotBlitzStatisticsPro.Blazor/Services/NotificationsService.cs

@@ -0,0 +1,42 @@
+using System;
+using WotBlitzStatisticsPro.Blazor.Model;
+
+namespace WotBlitzStatisticsPro.Blazor.Services
+{
+    public class NotificationsService: INotificationsService
+    {
+        // ToDo: Add JSInterop console.log
+
+        public NotificationType Type { get; private set; } = NotificationType.Info;
+        
+        public string Message { get; private set; } = string.Empty;
+
+        public string Summary { get; private set; }
+
+        public event Action MessageArrived;
+
+        public void ReportInfo(string summary, string message)
+        {
+            Type = NotificationType.Info;
+            Message = message;
+            Summary = summary;
+            MessageArrived?.Invoke();
+        }
+
+        public void ReportWarning(string summary, string message)
+        {
+            Type = NotificationType.Warning;
+            Message = message;
+            Summary = summary;
+            MessageArrived?.Invoke();
+        }
+
+        public void ReportError(string summary, string message)
+        {
+            Type = NotificationType.Error;
+            Message = message;
+            Summary = summary;
+            MessageArrived?.Invoke();
+        }
+    }
+}