L2SS-217: Run JIVE container on host network, instead of the custom NETWORK_MODE, to allow it to connect to DISPLAY.

L2SS-194: Build PCC & SDP devices explicitly, since docker compose doesn't understand running multiple services from a single local base image.

Use proc fs to access sysctl values, to be able to query whether the variables we want to write are exposed and writable at all.

Install software as root, so we can run processes in the container as any user and still have the software available to us.