Is there an automation that can dump all files in one business process into one folder in the file storage?

Hello. Unfortunately, there is no such functionality.
If such functionality is developed, then there are 2 options:
1. do multi-configuration of the ratios BP = directory in the system
and when adding a process to a process in a certain BP - the file is added to the corresponding directory
This modification will take 8 hours.
2. make an action (for example, a clock), in which there will be a multi-setting similar to paragraph 1
this action will be files created in the last hour, which have a link to the process - add a directory to the corresponding setting
This modification will take 6 hours.