Add physical color campaign workflow

[bestquark]

Summary

• turn the hardware objective into a small real LED/sensor experiment
• add a one-command physical BayesOpt campaign served on port 8000
• document the workshop flow from cloning through editing and running the campaign
• add workflow tests and LAN firewall configuration

Verification

• PYTHONPATH=src .venv/bin/python -m unittest discover -s tests -v
• git diff --check