node-vm: MAAS owns node power -- ignore_changes on running (operator-ruled) ...

The MAC-pin verification plan (docs/audit/inner-plan-20260721-macpin.txt,
0/9/0, 54 mac adoptions, zero replaces) exposed 9 entangled out-of-band
power-ons: the module re-asserts running=true against nodes MAAS holds
OFF. Operator-ruled: guard first, then apply.

- lifecycle ignore_changes = [running]: create still boots (PXE
  enlistment); afterwards MAAS owns power (virsh here, Roosevelt IPMI).
- tests/node-vm +3 cases (guard present, no scope creep, cites MAAS);
  15/15 green, gauntlet 73 ALL GREEN, repo-lint 0 fail.
- CURRENT-STATE: MAC-pinning delivery status + pending gated apply.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01STHXiHfoxHqq8fGRVvb66G