feat(bluetooth): add enable option

modules/bluetooth/default.nix

@@ -1,14 +1,23 @@
+{ lib, config, ... }:
+
+let
+  cfg = config.bluetooth;
+in
 {
-  hardware.bluetooth = {
-    enable = true;
-    powerOnBoot = true;
-    settings = {
-      General = {
-        Experimental = true;
-        FastConnectable = true;
-      };
-      Policy = {
-        AutoEnable = true;
+  options.bluetooth.enable = lib.mkEnableOption "bluetooth";
+
+  config = lib.mkIf cfg.enable {
+    hardware.bluetooth = {
+      enable = true;
+      powerOnBoot = true;
+      settings = {
+        General = {
+          Experimental = true;
+          FastConnectable = true;
+        };
+        Policy = {
+          AutoEnable = true;
+        };
       };
     };
   };