Reverse websocket is needed when the schedule job is not reachable (network wise) by the main web server. This setup is required on HPC (compute node vs login node) or with lambda like execution (target IP unkown). Then you need a proxy service to properly connect 2 client websocket connection together.
Are you asking me how to schedule a job on HPC and how you would make it work with trame?
Again that is to target 1 (or more) machine(s) per user rather than 1 process per user.
Based on what you said, it seems that you want 1 process for many users.