Regarding (1) one code file for the entire course or (2) one code file per video: First, I confess to not yet starting the course and, second, I have taken other code files when code files have been available both ways.
My preference is one code file per video. Often I don’t use the code file that comes with a video because I work with the video or pause the video to try to create the script before the video completes. If I had a very large file with all the scripts, I would find it annoying to search the file to extract the script of the moment. This search would be less annoying if each script had a great title block, but if the instructor fine-tunes the course by adding lessons over time, the code title would probably become wrong.
Thanks for asking.