feat: Tailscale VPN Setup

modules/default.nix

@@ -3,5 +3,6 @@
   imports = [
     ./environments
     ./hardware
+    ./services
   ];
 }

modules/services/default.nix

@@ -0,0 +1,8 @@
+# Service-related modules
+{ ... }:
+
+{
+  imports = [
+    ./vpn
+  ];
+}

modules/services/vpn/default.nix

@@ -0,0 +1,19 @@
+# self-hosted vpn
+{ config, lib, ... }:
+let
+  cfg = config.my.services.vpn;
+  inherit (config.networking) domain;
+in
+{
+  options.my.services.vpn = with lib; {
+    enable = mkEnableOption "Headscale VPN Setup";
+  };
+
+  config = lib.mkIf cfg.enable (
+    lib.mkMerge [
+      {
+        services.tailscale.enable = true;
+      }
+    ]
+  );
+}