Both Visual Studio 2013 and ReSharper offer many convenient shortcuts for refactoring code. One I commonly use is ReSharper's "Move String To Resource File", which moves a hard-coded string a *.resx file in your project.
Unfortunately, ReSharper doesn't provide "App.config" as an option among the list of resource files to move to.
Does anyone know how to enable or create a "Move/Convert String to App.Config Key" refactoring using either VS or ReSharper?
Config management is always going to be specific to the program, and in many cases the build system. Not all programs read strait from the app/web config. In fact sometimes you want to create a class or interface that provides your configuration options. As such,I don't think ReSharper is going to provide an easy way to do what your asking.
You can create a macro to move your text to be consistent with the config approach you have taken.However, its going to be a developers role to update the config value, and update the build variables(i.e if you have a config value for a connection string, that needs to be updated by the build system if moving between different builds).
If you do take the macro approach, you can put in a default value in your macro, so that the config overrides the default value, but you dont have to update the config.
i.e
ConfigurationManager.AppSettings["Config_value"]?? "Default_Value";