Both docker-compose files had a UID mismatch between the agent
(defaults to 10000) and webui (defaults to 1000). When containers
share a volume, the webui gets Permission denied reading files
written by the agent.
- docker-compose.two-container.yml: add HERMES_UID/HERMES_GID
(was missing entirely)
- docker-compose.three-container.yml: change default from 10000
to 1000 to match webui's WANTED_UID/WANTED_GID
Fixes#1399
