How to include my App.Config file and classes into single DLL

I have a class library project with routines, classes and a Entity Framework connected to do update the database.

The project structure looks like this:

and my Output looks like this:

I would like to have a single DDL output, like ServiceRoutine.dll, with all the Project output files including the the project config files.

The reason for this is, we need to deploy this service on a clients server, on premises and want a single DLL with no exposed code, configs or any other file they can mess with.

Any idea how to archive this?