DOCFIX-144: opentofu/modules/node-vm + fix real syntax bug in DOCFIX-142 ...

Built the D-103 node-VM pattern (blank disk, PXE-boot, MAAS-managed) for
Stage 3 -- this time from the provider's own real example .tf files
(examples/domain_with_network.tf, examples/alpine_cloudinit.tf), not
doc-summarization alone, since that confidence gap is exactly why the domain
module was deferred last time.

That surfaced a real bug in the already-pushed dc-planes/mesh-link/
dc-storage-pool modules (14d7382): they used classic HCL block syntax
(domain { ... }) where this provider's current schema needs attribute-style
objects (domain = { ... }) -- confirmed once real examples showed the actual
convention. All three fixed; opentofu/README.md's schema notes now state this
as a provider-wide assumption for any field not personally confirmed
otherwise.

One inference flagged, not presented as fact: the per-device boot-order
attribute's exact internal shape ({ order = N }) -- the field's existence is
confirmed, its shape is not. Not instantiated in root main.tf: node
count/sizing is a pending Phase-0 decision, not invented here. Still
deferred: the cloud-init/base-image VM pattern (Office1 services + OPNsense),
DC2 planes, netem application.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01QrcJx8TUar7pYAvpGJw57A

DOCFIX-142: opentofu/ network + storage-pool scaffold (VR1 IaC, gap #2) ...

First OpenTofu content in the repo. Network/pool layer only: modules/dc-planes
(the six per-DC planes, D-052/D-100), modules/mesh-link (the D-100 dark-fiber
triangle), modules/dc-storage-pool, wired for DC1 (inherits DC0's CIDRs per
D-101) and Office1. DC2 deliberately not wired -- its CIDRs aren't assigned
yet (D-101 open sub-item).

Provider schema (dmacvicar/libvirt v0.9.8) verified against its actual current
docs this session, not memory -- it has diverged materially from older common
examples (network isolation is a nested forward.mode, not top-level mode;
libvirt_domain restructured to ~40 args mirroring raw libvirt XML). Node-VM/
volume resources, OPNsense config, and tc netem application are deliberately
deferred: that schema is too large/unfamiliar to author safely without a real
`tofu providers schema` pass on a connected machine -- see opentofu/README.md
for the full account and the concrete next step.

Added scripts/opentofu-validate.sh (fmt/init/validate wrapper) + a harness
testing what's actually exercisable without a tofu binary (none is available
anywhere this repo has been worked in this session -- logged, not hidden).
Extended repo_lint.py's L1 check to cover .tf files (uncovered before since
none existed). repo-lint 0 fail / 1 documented warn; both harnesses green.
Workflow doc + its companion visual tracker updated to match.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01QrcJx8TUar7pYAvpGJw57A