infra: join ludo-mini to hubris as Homelab cluster node "strong"

Reformatted the ludo-mini workstation to Proxmox VE 9.2.3 and joined it
to hubris's existing single-node "Homelab" cluster (2 nodes, no QDevice
yet). Added a second NVMe as its own LVM-thin pool (ludo-lvm). Renamed
the wiki/inventory identity from ludo-mini to strong to match the OS/
cluster hostname, since bootstrap's client-enrollment lookup depends on
that match. Also regenerated hosts/grimmory.yaml, which was missing from
git despite being referenced by inventory.yaml.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

README.md

@@ -7,7 +7,8 @@ Living documentation for the **hubris** Proxmox homelab. Every node, every cross
 ## Map
 
 ### Hosts
-- [`hubris`](hosts/hubris.md) — single Proxmox VE node, GMKtec NucBox M6 Ultra, `192.168.8.77`
+- [`hubris`](hosts/hubris.md) — Proxmox VE node, GMKtec NucBox M6 Ultra, `192.168.8.77` — runs everything today
+- [`strong`](hosts/strong.md) — Proxmox VE node (cluster hostname `strong`), `192.168.178.181` — 2nd member of the `Homelab` cluster as of 2026-07-01, hosts no guests yet
 
 ### VMs
 - [100 — `zimaos`](vms/100-zimaos.md) — ZimaOS 1.6.1, NAS frontend (evaluation)