Make audiobookshelf togglable per host

nix/modules/nixos/features/homelab/audiobookshelf.nix

@@ -1,6 +1,14 @@
-{ config, ... }:
+{ config, lib, ... }:
 
+with lib;
+
+let
+  cfg = config.features.homelab.audiobookshelf;
+in
 {
+  options.features.homelab.audiobookshelf.enable = mkEnableOption "Enable audiobookshelf";
+
+  config = mkIf cfg.enable {
     services.audiobookshelf = {
       enable = true;
 
@@ -18,4 +26,5 @@
         };
       };
     };
+  };
 }