Unattended OPNsense provisioning for Proxmox VE via standard NoCloud
cloud-init. Automates OPNsense's normally-manual bring-up: install from ISO,
assign LAN, and configure interfaces/addressing/VLANs/SSH — everything the
setup wizard would otherwise ask for by hand — by parsing a standard
Proxmox NoCloud seed and rendering it directly into /conf/config.xml. No
cloud-init package ever runs inside the guest.