refactor: make the whole thing more generic

modules/home-manager/services/default.nix

@@ -0,0 +1,12 @@
+{ pkgs, homeDirectory, ... }: {
+  services = {
+    gpg-agent = {
+      enable = true;
+      enableSshSupport = true;
+      pinentryPackage = pkgs.pinentry-gnome3;
+    };
+    # fix pinentry on non-gnome with this in
+    # the system config: services.dbus.packages = with pkgs; [ gcr ];
+    gnome-keyring.enable = true;
+  };
+}