Including shortcodes in every file

[pgorod]

I am wondering if there is a nice way for us to have a standard include at the beginning of every file, where we could place initial definitions like :experimental:, imagesdir, or even those more complex ifdef blocks that are in the Russian files.

This might help:

https://discourse.gohugo.io/t/include-file-shortcode-for-including-files-with-shortcode-calls/16699

I would be especially interested if these could be made "intelligent", meaning, if I could use Hugo logic to sort out which parts to include according to the file from which it is being included; and to set up an appropriate imagesdir, for example.