Add kube-proxy.

nix/kubernetes/roles/kubernetes/default.nix

@@ -18,6 +18,14 @@
   };
 
   config = lib.mkIf config.me.kubernetes.enable {
+    assertions = [
+      {
+        # Kubernetes should only upgrade 1 minor version at a time, so this assert is here to prevent unwittingly jumping versions.
+        assertion = lib.hasPrefix "1.35." pkgs.kubernetes.version;
+        message = "Unexpected Kubernetes package version: ${pkgs.kubernetes.version}";
+      }
+    ];
+
     environment.systemPackages = with pkgs; [
       kubernetes
     ];