Configures a pod's network namespace at the Linx.Process :ready checkpoint. A pod's :network is one of:

• :host — the workload shares the host's network namespace (the runtime simply doesn't give it a fresh :net ns), so there is nothing to do here.
• :none — an isolated netns with loopback only.
• %Tank.Pod.Network{} — loopback plus one or more %Tank.Nic{}.

Each macvlan NIC is created in the host netns over its parent uplink, then moved into the container's netns, and renamed / addressed / brought up there — a macvlan can't be created directly in the container over a parent that lives in the host netns. The host-side name is transient because the final name (e.g. eth0) usually collides with a host interface.

DNS (/etc/resolv.conf) is materialised by the orchestrator (Tank.Runtime) during rootfs setup, not here.