refactor: moved server module configs out of default.nix files

modules/nixos-modules/server/actual/actual.nix

@@ -0,0 +1,20 @@
+{
+  lib,
+  config,
+  ...
+}: let
+  const = import ./const.nix;
+  dataDirectory = const.dataDirectory;
+in {
+  config = lib.mkIf config.services.actual.enable {
+    systemd.tmpfiles.rules = [
+      "d ${dataDirectory} 2770 actual actual"
+    ];
+
+    services.actual = {
+      settings = {
+        ACTUAL_DATA_DIR = dataDirectory;
+      };
+    };
+  };
+}