chore: updated readme

Author: rajamatt

reference/Counter/README.md

@@ -3,4 +3,21 @@
 Discover the simplicity and power of Uno.Extensions with the Counter App, a straightforward yet powerful demonstration of basic and advanced features of the Uno Platform. This app provides a hands-on experience with fundamental concepts such as state management, user interaction, and UI updates in real-time.
 This sample app was built using the four variants of the [Counter workshop](https://aka.platform.uno/counter-tutorial), combining markup language (XAML or C# Markup) and presentation framework (MVVM or MVUX).
 
-![CounterApp Image](doc/assets/counterApp.png)
+![CounterApp Image](doc/assets/counterApp.png)
+
+## Codebase
+
+### MVVM
+
+* [**C#-MVVM MainViewModel.cs**](CSharp-MVVM/Counter/MainViewModel.cs) C#-MVVM model with [**C#-MVVM MainPage.cs**](CSharp-MVVM/Counter/MainPage.cs) C#-MVVM data binding.
+* [**XAML-MVVM MainViewModel.cs**](XAML-MVVM/Counter/MainViewModel.cs) XAML-MVVM model with [**XAML-MVVM MainPage.xaml**](XAML-MVVM/Counter/MainPage.xaml) XAML-MVVM data binding.
+
+### MVUX
+
+* [**C#-MVUX MainModel.cs**](CSharp-MVUX/Counter/MainModel.cs) C#-MVUX states and record immutability with [**C#-MVUX MainPage.cs**](CSharp-MVUX/Counter/MainPage.cs) C#-MVUX data binding.
+* [**XAML-MVUX MainViewModel.cs**](XAML-MVUX/Counter/MainModel.cs) XAML-MVUX states and record immutability with [**XAML-MVUX MainPage.xaml**](XAML-MVUX/Counter/MainPage.xaml) XAML-MVUX data binding.
+
+## What is the Uno Platform
+
+[Uno Platform](https://platform.uno) is an open-source .NET platform for building single codebase native mobile, web, desktop, and embedded apps quickly.
+For additional information about Uno Platform or if you have any feedback to share, please refer to the [README.md](../../README.md) file in this Samples repository.