feat(k8s): declare 'crossplane' module

home/modules/k8s/crossplane.nix

@@ -0,0 +1,12 @@
+{
+  config,
+  lib,
+  pkgs,
+  ...
+}:
+
+{
+  config = lib.mkIf config.k8s.crossplane.enable {
+    home.packages = [ pkgs.upbound ];
+  };
+}