Dockerize `ib-gw` 🏄🏼

[goodboy]

Based on the now defunct project @ https://github.com/waytrade/ib-gateway-docker

Adds a docker-compose.yml and necessary gateway and IBC config files to make it possible to spin up a local gateway on localhost:4002 and connect to it without issue using ib_insync.

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TODO: container POC config

• [ ] ~add a api socket blackhole for anything but connections from localhost~ bleh we can't; no iproute2 installed in this image...:
  • ip rule add blackhole iif <docker_net_iface_name> to 0.0.0.0/0 dport 4002
  • ip rule add not unicast iif lo to 0.0.0.0/0 dport 4002 actually this is probably better since it's the inverse and requires no net iface info
• [ ] figure out why the vnc auth still doesn't seem to be working?
• [x] clarify the vnc port setting (explained in readme from 48a8174)

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In a follow up PR, we'll want to,

• automated the equivalent docker-compose steps using our .data._ahab supervisor system
• probably simplify and roll our own container (likely alpine or nixos based) which drops uneeded deps (socat, vnc) and adds xdotool.
• allow for API socket mapping to just be pulled direct from a user's brokers.toml and we'll just pass that direct to IBC's config.

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Follow up TODOs for windows:

For extra lolz, you can't use --net=host on windows as per:

• https://docs.docker.com/network/host/

  The host networking driver only works on Linux hosts, and is not supported on Docker Desktop for Mac, Docker Desktop for Windows, or Docker EE for Windows Server.

So that means we'll need to:

• [ ] either go back to the socat stuff from the original container from waytrade
• [ ] use a bridge network inside the container namespace and do sensible routing table to map the necessary vnc and gw ports

I'm thinking latter is better and we can just configure this dynamically if/when we do container running from our ._ahab.py supervisor daemon.

[goodboy]

All other unchecked tasks moved to #329 FYI