Removes socat, openssh-client, and dnsutils from Dockerfile.claude
and Dockerfile.codex.
- socat was the privileged forwarder for the in-container ssh-agent
that PRD 0009 removed; nothing in bot_bottle references it.
- openssh-client was needed back when the agent talked ssh:// to
upstreams; git-gate's insteadOf rewrites now route every upstream
through HTTP/git-protocol, and ssh-keygen runs host-side from the
deploy-key provisioner.
- dnsutils was only used by tests/integration/test_sandbox_escape.py
(attack 4b runs dig from inside the agent container).
Splits python3/python3-pip/python3-venv onto a separate layer with
a comment noting they're app-specific and a candidate to move to a
downstream image.
didericis-claude