DOCFIX-188: root-cause the OPNsense boot triple-fault -- libvirt memory_unit (guest had 2 MiB) ...

The 2026-07-12 triple-fault was never a CPU/nesting/machine/console problem.
dmacvicar/libvirt >=0.9 reinterprets `memory` as raw libvirt units (KiB), not
MiB (the 0.8-era meaning the modules were authored against). With no
`memory_unit`, `memory = 2048` rendered `<memory unit='KiB'>2048</memory>` ->
QEMU `-m size=2048k` = 2 MiB. boot2 fits in 2 MiB and echoes /boot.config;
/boot/loader does not -- hence the deterministic 262-byte fault, immune to every
knob the prior window turned.

Measured every hop: module input -> tofu state -> domain XML -> virsh dominfo
(Max memory: 2048 KiB) -> live QEMU cmdline.

FOUNDATIONAL: the identical defect was latent in all three VM modules --
opnsense-edge (live blocker), cloudinit-vm (MAAS/NetBox/GitBucket, the next
step), node-vm (Stage 3). Every VR1 VM would have gotten 1024x too little RAM.

- memory_unit = "MiB" on all three libvirt_domain resources (memory_mib = 2048
  value untouched -- it now means the 2 GiB always intended).
- Corrected the disproven "svm is ROOT CAUSE" comment in opnsense-edge; the
  setting is retained as legitimate hardening, the false claim is not.
- Guard: opentofu-validate.sh S1 + --check-memory-unit flag. `tofu validate`
  cannot catch this (memory_unit is optional => omitting it is schema-valid,
  which is exactly how it shipped). Harness T3 is a true negative test: the
  fixture IS the shipped defect. Harness 1 -> 4 PASS.
- Incident report gains a READ-THIS-FIRST box so nobody re-chases the CPU theories.

Gauntlet ALL GREEN (52 harnesses); repo-lint 0 fail; tofu fmt/validate clean.
Live boot verification remains a separately-gated operator step.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Y117t1F525ba9r1vXSBETk

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