SWE-Atlas QnA network-policy derivative

SWE-Atlas QnA @1, network-policy-only derivative is materialized from the Harbor source package scale-ai/swe-atlas-qna@1, which comes from scaleapi/SWE-Atlas commit b0611b05a9f4f09b25aafad96617f9ec64ad722b.

Each source task receives exactly four changes:

1. schema_version = "1.1" becomes schema_version = "1.4".
2. [agent] receives network_mode = "allowlist" and allowed_hosts = [].
3. [environment] replaces allow_internet = true with network_mode = "public".
4. environment/docker-compose.yaml clears the prebuilt image entrypoint so Harbor's native keepalive command runs unchanged.

All other files and bytes are preserved. Materialize and verify with:

python scripts/materialize.py "$ATLAS_SOURCE" tasks
python scripts/materialize.py --verify "$ATLAS_SOURCE" tasks