the most practical solution for BPM-server Scripting is to store these System specific "configurations" in seperate Files in the folder <dms-service-install-dir>\standalone\configuration\bpm-script-api\lib.
The files can be used in the BPM-Server Scripting using
load($.LIB_PATH + '<file-name>');
to get these infos in the BPM-client context you can store it to a variable and use that one in the client context
for forward options in bpm-context unfortunanly there is no reasonable way to achieve that.
for custom actions in general client context you would have to get these informations from a central service and load it. I guess a small microservice to achieve that is in order.
I must admitt, that I never did that myself. In theory, if you have this in place it would also be a better way to handle client scripting in bpm contexts, maybe even the servers side scripting configurations.
the idea to provide you with such a service has been around for quite a while but as far as i know we didn't deliver it yet. So my recommendation is to write it yourself and centralise all your system specific configurations there.