feat(uptime-kuma): add enable option

modules/uptime-kuma/default.nix

@@ -1,9 +1,14 @@
 {
+  lib,
+  config,
   pkgs,
   ...
 }:
 
 {
+  options."uptime-kuma".enable = lib.mkEnableOption "uptime-kuma";
+
+  config = lib.mkIf config."uptime-kuma".enable {
     virtualisation.oci-containers = {
       backend = "docker";
       containers.uptime-kuma = {
@@ -27,4 +32,5 @@
     };
 
     environment.systemPackages = with pkgs; [ docker-compose ];
+  };
 }