Added color themes (dark & light) (#148)

app/MindWork AI Studio/Settings/DataModel/ThemesExtensions.cs

@@ -0,0 +1,16 @@
+namespace AIStudio.Settings.DataModel;
+
+public static class ThemesExtensions
+{
+    public static string GetName(this Themes theme)
+    {
+        return theme switch
+        {
+            Themes.SYSTEM => "Synchronized with the operating system settings",
+            Themes.LIGHT => "Always use light theme",
+            Themes.DARK => "Always use dark theme",
+            
+            _ => "Unknown setting",
+        };
+    }
+}