feat: refactor infra to cp/wk kubeadm topology

Provision 3 thin control planes and 3 workers with role-specific sizing and VMID ranges (701/711), generate per-node cloud-init snippets with SSH key injection, and add NixOS kubeadm host/module scaffolding for cp-1..3 and wk-1..3.

nixos/kubeadm/hosts/cp-1.nix

@@ -0,0 +1,14 @@
+{ lib, ... }:
+
+{
+  imports =
+    [
+      ../modules/k8s-common.nix
+      ../modules/k8s-control-plane.nix
+    ]
+    ++ lib.optional (builtins.pathExists ./hardware/cp-1.nix) ./hardware/cp-1.nix;
+
+  networking.hostName = "cp-1";
+
+  system.stateVersion = "25.05";
+}

nixos/kubeadm/hosts/cp-2.nix

@@ -0,0 +1,14 @@
+{ lib, ... }:
+
+{
+  imports =
+    [
+      ../modules/k8s-common.nix
+      ../modules/k8s-control-plane.nix
+    ]
+    ++ lib.optional (builtins.pathExists ./hardware/cp-2.nix) ./hardware/cp-2.nix;
+
+  networking.hostName = "cp-2";
+
+  system.stateVersion = "25.05";
+}

nixos/kubeadm/hosts/cp-3.nix

@@ -0,0 +1,14 @@
+{ lib, ... }:
+
+{
+  imports =
+    [
+      ../modules/k8s-common.nix
+      ../modules/k8s-control-plane.nix
+    ]
+    ++ lib.optional (builtins.pathExists ./hardware/cp-3.nix) ./hardware/cp-3.nix;
+
+  networking.hostName = "cp-3";
+
+  system.stateVersion = "25.05";
+}

nixos/kubeadm/hosts/wk-1.nix

@@ -0,0 +1,14 @@
+{ lib, ... }:
+
+{
+  imports =
+    [
+      ../modules/k8s-common.nix
+      ../modules/k8s-worker.nix
+    ]
+    ++ lib.optional (builtins.pathExists ./hardware/wk-1.nix) ./hardware/wk-1.nix;
+
+  networking.hostName = "wk-1";
+
+  system.stateVersion = "25.05";
+}

nixos/kubeadm/hosts/wk-2.nix

@@ -0,0 +1,14 @@
+{ lib, ... }:
+
+{
+  imports =
+    [
+      ../modules/k8s-common.nix
+      ../modules/k8s-worker.nix
+    ]
+    ++ lib.optional (builtins.pathExists ./hardware/wk-2.nix) ./hardware/wk-2.nix;
+
+  networking.hostName = "wk-2";
+
+  system.stateVersion = "25.05";
+}

nixos/kubeadm/hosts/wk-3.nix

@@ -0,0 +1,14 @@
+{ lib, ... }:
+
+{
+  imports =
+    [
+      ../modules/k8s-common.nix
+      ../modules/k8s-worker.nix
+    ]
+    ++ lib.optional (builtins.pathExists ./hardware/wk-3.nix) ./hardware/wk-3.nix;
+
+  networking.hostName = "wk-3";
+
+  system.stateVersion = "25.05";
+}