I think you are asking if you update your file without doing a deployment you would have to only upload it once and all environments share the same resource folder? The answer is no. If you want to update a file in the resource folder without doing a deployment, you would have to upload the new file to each environment.
I don't think there is a way to setup a listener but what you could do is expose the microflow that processes your logic with a rest service, and then you can just call the rest service once you update your file and it will rerun the logic.
Here is the documentation for publishing a rest service.
Hope this helps!