Creé una carpeta pública con el activo de nombre y creé dos rutas adminroute y category route.

 Admin route file const express=require('express') const path=require('path') const adminRoute=express() const session =require( 'express-session') const config =require('../config/config') adminRoute.use(session({ secret: config.sessionSecret, resave: true, saveUninitialized: true,cookie:{secure:false,maxAge:60000} })); const bodyParser=require( 'body-parser') adminRoute.use(bodyParser.urlencoded({extended:false})); adminRoute.set('view engine','ejs'); adminRoute.set('views','./views/admin'); const adminController =require( '../controller/adminController') //const auth=require('../middleware/adminAuth') adminRoute.get('/',adminController.loadLogin); adminRoute.post('/',adminController.verifyLogin); adminRoute.get('/home',adminController.loadDashboard); adminRoute.get('/register',adminController.register); adminRoute.post('/register',adminController.doRegister); adminRoute.get('/logout',adminController.logout ); const users=require('./userRoute') adminRoute.use('/users',users) const category=require('./categoryRoute') adminRoute.use('/categories', category); adminRoute.get('*',function(req,res){ res.redirect('/admin') }) module.exports =adminRoute Category route file const express=require('express') const path=require('path') console.log(path.join(__dirname + '/../assets')) const catRoute=express(); const categoryController=require('../controller/categoryController') ; const session =require( 'express-session') const config =require('../config/config') catRoute.use(session({ secret: config.sessionSecret, resave: true, saveUninitialized: true,cookie:{secure:false,maxAge:60000} })); const bodyParser=require( 'body-parser') catRoute.use(bodyParser.urlencoded({extended:false})); catRoute.set('view engine','ejs'); catRoute.set('views','./views/admin'); //const auth=require('../middleware/adminAuth') catRoute.use(express.static(path.join(__dirname + '/../assets'))); catRoute.get('/',categoryController.loadCategories); catRoute.get('/add',categoryController.loadAddCategory); module.exports=catRoute

ambas rutas usando diferentes carpetas públicas.

Ruta de administración: - http://localhost:3000/vendor/libs/jquery/jquery.js

Ruta de gato: - http://localhost:3000/admin/vendor/libs/jquery/jquery.js

sugiera por qué la ruta del gato usa la carpeta principal (administrador) como carpeta pública al acceder a js en el archivo ejs.