Scaffold Cloudron packaging workspace and automation

docker/ci-runner/Dockerfile

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+# CI harness image mirroring the Actions environment used by act_runner
+FROM ghcr.io/catthehacker/ubuntu:act-22.04
+
+ENV DEBIAN_FRONTEND=noninteractive
+
+RUN apt-get update \
+    && apt-get install --yes --no-install-recommends \
+       ca-certificates \
+       curl \
+       git \
+       gnupg \
+       jq \
+       make \
+       python3 \
+       python3-pip \
+       python3-venv \
+       docker.io \
+    && rm -rf /var/lib/apt/lists/*
+
+# Configure git to trust any mounted workspace path inside the container
+RUN git config --system --add safe.directory '*'
+
+WORKDIR /workspace
+
+ENTRYPOINT ["/bin/bash", "-lc"]
+CMD ["sleep infinity"]