feat(system): menu parity for downstream options (slice 1)

Added toggles for updates, battery limit, bluetooth, and printing to the Control Center. Wired default values to read from theme-state.json settings. Verified: V1.

modules/nixos/options.nix

@@ -3,7 +3,7 @@
 # Deliberately small: only things a downstream user plausibly disagrees
 # with get a toggle. Everything else in the system module is set with
 # lib.mkDefault, so plain NixOS options override it natively.
-{ lib, ... }:
+{ config, lib, ... }:
 
 {
   options.nomarchy.system = {
@@ -44,7 +44,7 @@
       option'' // { default = true; };
 
     audio.enable = lib.mkEnableOption "the Pipewire audio stack" // { default = true; };
-    bluetooth.enable = lib.mkEnableOption "Bluetooth support with blueman" // { default = true; };
+    bluetooth.enable = lib.mkEnableOption "Bluetooth support with blueman" // { default = config.nomarchy.settings.bluetooth.enable or true; };
 
     autoTimezone.enable = lib.mkEnableOption ''
       automatic timezone detection (geoclue + automatic-timezoned): the
@@ -102,7 +102,7 @@
 
       batteryChargeLimit = lib.mkOption {
         type = lib.types.nullOr (lib.types.ints.between 50 100);
-        default = null;
+        default = config.nomarchy.settings.power.batteryChargeLimit or null;
         example = 80;
         description = ''
           Stop charging at this percentage to extend battery lifespan,