migrate to "export default"

also, set no-use-before-define in linter

src/directoryserver.js

@@ -4,30 +4,21 @@ import BoxError from './boxerror.js';
 import constants from './constants.js';
 import debugModule from 'debug';
 import eventlog from './eventlog.js';
-import * as ipaddr from './ipaddr.js';
-import * as groups from './groups.js';
+import ipaddr from './ipaddr.js';
+import groups from './groups.js';
 import ldap from 'ldapjs';
 import path from 'node:path';
 import paths from './paths.js';
-import * as reverseProxy from './reverseproxy.js';
+import reverseProxy from './reverseproxy.js';
 import safe from 'safetydance';
-import * as settings from './settings.js';
+import settings from './settings.js';
 import shellModule from './shell.js';
-import * as users from './users.js';
+import users from './users.js';
 import util from 'node:util';
 
 const debug = debugModule('box:directoryserver');
 const shell = shellModule('directoryserver');
 
-export {
-    getConfig,
-    setConfig,
-
-    start,
-    stop,
-
-    checkCertificate,
-};
 
 let gServer = null, gCertificate = null;
 
@@ -414,3 +405,13 @@ async function checkCertificate() {
     await stop();
     await start();
 }
+
+export default {
+    getConfig,
+    setConfig,
+
+    start,
+    stop,
+
+    checkCertificate,
+};