Certainly a script could do this. Is that what you are asking, whether a script can do it? Or are you asking for a script? I don't know if anyone will provide one for free.
I believe a script could invoke the Save All Files command directly with an FCode. Alternatively, if you don't like FCodes, it could iterate over all book components, retrieve the corresponding document filenames, look for the docs in the interface, then save them. That would be more than a few lines.
Why would you need a script to do something that is quite easily supported in the GUI. You mention Shift_Ctrl, which seems to indicate that you are trying to select files in the book window before executing the Save command. When the book window is active and you press Shift before opening the FIle menu, you will have a command to save all components of the book in one go.
If you had a script you would have to go through File > Script > Run, select the script and run it. How is that going to save you any effort or time?
In short - the use case is not at all clear from your description. Let us know what your requirements are in more detail. Depending on those, you might either not need a script at all or know how to create one.