Repair CI build job for current GitHub Actions runner and Docker image builds

[Copilot]

The build GitHub Actions job was failing on the current runner image because it invoked the removed docker-compose binary. While validating the build path, the Docker image build also surfaced a few broken assumptions in the repository’s container configuration.

• CI workflow

  • Switched the build job from the legacy Compose v1 binary to the supported Compose v2 CLI:

    - name: Build Docker images
      run: |
        docker compose -f docker-compose.dev.yml build

• Worker image build

  • Added the tracked mohawk_gui/config.toml template expected by Dockerfile.worker
  • Moved onnxruntime installation out of apt and into pip, matching how the dependency is actually distributed

• Controller image build

  • Installed curl, which is required by the existing liboqs install step and healthcheck
  • Fixed non-root user creation by creating the group before adding the user

• Net effect

  • The Actions build job now uses the runner-supported Compose command
  • docker-compose.dev.yml builds no longer fail on missing config, invalid package installation, or controller user setup