There is no step-by-step guide.
If you want to extract the application from the SDK you can achieve this by creating your own script/ software to transform the typescript from the SDK to functional (java) code. The SDK contains all the information you would need to recreate the application outside the Mendix runtime, although this is not a straightforward task as you would need to device a way to convert the SDK data and the functions of the Mendix runtime to obtain a fully functional application