Enable Homebrew for aarch64-darwin

Added configuration to enable Homebrew on aarch64-darwin systems. Created a new module for managing Homebrew settings and added support for declarative tap management.

modules/darwin/system/homebrew/default.nix

@@ -0,0 +1,38 @@
+{ lib, config, inputs, ... }:
+
+with lib;
+with lib.metacfg;
+let
+  cfg = config.metacfg.system.fonts;
+in
+{
+  imports = [ inputs.nix-homebrew.darwinModules.nix-homebrew ];
+
+  options.metacfg.system.homebrew = with types; {
+    enable = mkBoolOpt false "Whether or not to enable homebrew";
+  };
+  config = mkIf cfg.enable {
+    nix-homebrew = {
+      # Install Homebrew under the default prefix
+      enable = true;
+
+      # Apple Silicon Only: Also install Homebrew under the default Intel prefix for Rosetta 2
+      enableRosetta = false;
+
+      # User owning the Homebrew prefix
+      user = "harald";
+
+      # Optional: Declarative tap management
+      taps = {
+        "homebrew/homebrew-core" = inputs.homebrew-core;
+        "homebrew/homebrew-cask" = inputs.homebrew-cask;
+        "homebrew/homebrew-bundle" = inputs.homebrew-bundle;
+      };
+
+      # Optional: Enable fully-declarative tap management
+      #
+      # With mutableTaps disabled, taps can no longer be added imperatively with `brew tap`.
+      mutableTaps = false;
+    };
+  };
+}

systems/aarch64-darwin/m4/default.nix

@@ -2,7 +2,14 @@
 
 with lib.metacfg;
 {
+
+  homebrew = {
+    enable = true;
+    brews = [ "libusb"];
+  };
+
   metacfg = {
+    system.homebrew = enabled;
     suites = {
       common = enabled;
     };