Shape taken from the provider schema (devices.channels[].target.virt_io /
source.unix on dmacvicar 0.9.8), not inferred. Default OFF so existing
edges are never bounced by a plan; the new dc0 edge boots with it per the
runbook's no-retrofit intent for NEW DC edges. Without the channel the
os-qemu-guest-agent package is inert-but-present -- the false success the
D-129 review flagged -- so package and channel ship as one decision.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01KiUu1oqt76tWvV4vEC3NAr