Show LLM provider issues to the user (#384)

app/MindWork AI Studio/Tools/Error.cs

@@ -0,0 +1,16 @@
+namespace AIStudio.Tools;
+
+public readonly record struct Error(string Icon, string Message)
+{
+    public void Show(ISnackbar snackbar)
+    {
+        var icon = this.Icon;
+        snackbar.Add(this.Message, Severity.Error, config =>
+        {
+            config.Icon = icon;
+            config.IconSize = Size.Large;
+            config.HideTransitionDuration = 600;
+            config.VisibleStateDuration = 14_000;
+        });
+    }
+}

app/MindWork AI Studio/Tools/Event.cs

@@ -9,6 +9,7 @@ public enum Event
     CONFIGURATION_CHANGED,
     COLOR_THEME_CHANGED,
     PLUGINS_RELOADED,
+    SHOW_ERROR,
     
     // Update events:
     USER_SEARCH_FOR_UPDATE,

app/MindWork AI Studio/Tools/MessageBus.cs

@@ -65,7 +65,9 @@ public sealed class MessageBus
             this.sendingSemaphore.Release();
         }
     }
-    
+
+    public Task SendError(Error error) => this.SendMessage(null, Event.SHOW_ERROR, error);
+
     public void DeferMessage<T>(ComponentBase? sendingComponent, Event triggeredEvent, T? data = default)
     {
         if (this.deferredMessages.TryGetValue(triggeredEvent, out var queue))