feat: add tailscale module

modules/tailscale/default.nix

@@ -0,0 +1,17 @@
+{
+  lib,
+  config,
+  ...
+}:
+{
+  options.tailscale = {
+    enable = lib.mkEnableOption "tailscale";
+  };
+
+  config = lib.mkIf config.tailscale.enable {
+    services.tailscale = {
+      enable = true;
+      openFirewall = true;
+    };
+  };
+}