refactor!: remove MetalLB

Replaced by Cilium L2 Aware LB.

Additionally, the default Zerotier route was changed to match the
LB IP pool rather than the entire home subnet. This makes it easier
to manage in the configure script and can be updated to any value
later if needed.

docs/reference/architecture/overview.md

@@ -62,7 +62,6 @@ flowchart TD
   end
 
   subgraph system[./system]
-    metallb[MetalLB]
     nginx[NGINX]
     longhorn[Longhorn]
     cert-manager
@@ -137,9 +136,7 @@ Below is the pseudo code for the entire process, you don't have to read it right
                 copy k3s config files
                 enable k3s service and form a cluster
                 create KUBECONFIG file
-                create MetalLB config:
-                    use the last /27 subnet of the network
-                    apply the config
+                install Cilium
         build ./bootstrap:
             install ArgoCD:
                 apply helm chart