use node: prefix for requires

mostly because code is being autogenerated by all the AI stuff using
this prefix. it's also used in the stack trace.

src/oidcclients.js

@@ -16,7 +16,7 @@ exports = module.exports = {
     ID_SDK: 'cid-sdk',                  // created by user via dashboard
 };
 
-const assert = require('assert'),
+const assert = require('node:assert'),
     BoxError = require('./boxerror.js'),
     dashboard = require('./dashboard.js'),
     database = require('./database.js'),