DOCFIX-148: OpenTofu module audit pass + provider-docs skill reference ...

Audited every "UNVERIFIED"/"inferred"/"assumed" marker across all 9 modules
built this session rather than leaving them as-is. Found and fixed a real
documentation error: opnsense-edge's comments claimed devices.interfaces
list order directly sets OPNsense's LAN/WAN role. Researching OPNsense's own
interface-assignment model showed this conflates two things -- list order
plausibly controls which vtnetN device number a NIC gets (libvirt's own
docs: auto-assigned PCI addresses "usually match" XML order for a simple
topology), but the actual LAN/WAN role is a separate, explicit mapping set
inside config.xml itself ("vtnet0=WAN" is a convention some guides choose,
not an enforced rule). Corrected main.tf's comments and both
lan_network_name/wan_network_name variable descriptions -- no config.xml
exists in this repo yet, so this fixes documentation accuracy for whoever
writes it next, not current behavior.

Confidence upgraded (not just re-hedged) on three other items: node-vm's
boot={order=N} shape (confirmed the provider 1:1-mirrors libvirt's own XML,
and libvirt's own docs confirm the single-attribute shape), create.content.url
accepting local paths (second independent source), and the genisoimage
flags (confirmed standard, cleanly separated from the still-open question of
whether OPNsense's Importer actually reads the result). Confirmed safe:
maas_vm_host's zone/pool computed-if-unset behavior.

Added .claude/skills/openstack-cloud-ops/references/opentofu-provider-docs.md:
indexes every provider/doc source used this session with exact URLs and
confirmed versions, plus the fetch methodology that actually worked
(Registry doc pages are JS-rendered, use GitHub instead; branch names vary,
check default_branch via the API; real example .tf files beat doc-summarized
prose for syntax questions). Wired into SKILL.md's routing table,
cross-referenced from opentofu/README.md in both directions without
duplicating content.

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