Add UML Diagram for External Intfs

[hhenry01]

Description

• Resolves Replace external interfaces table with UML diagram #22
• Blocked by Plantuml Infrastructure sailbot_workspace#212 and Updated readme & Added new .msg for CAN transceiver / Simulation Interface #28
• Also removed Local Transceiver as one of the subscribers for filtered_wind_sensors because I think it's an unnecessary extra amount of data we'd need to transmit over satellite (more $$$)
• I think uploading the rendered diagram to github and rendering it in the README is helpful.

Verification

• Renders as:
  

Resources

• https://plantuml.com/state-diagram

[hhenry01]

There's currently some confusion over the status of the global_path topic using a msg or a service, so I'm waiting on that to resolve before continuing.

[hhenry01]

I'm guessing the other interface tables are simple enough to understand without a diagram. Alternatively we could make one of the members do the other diagrams.

[patrick-5546]

LGTM, will also want to verify that this renders correctly on docs site once merged in

[hhenry01]

It does not render on the docs site.