challenge-11/models/User.js

const mongoose = require('mongoose');

const userSchema = new mongoose.Schema({
  username: {
    type: String,
    required: true,
    unique: true
  },
  password: {
    type: String,
    required: true
  },
  role: {
    type: String,
    enum: ['admin', 'staff'],
    default: 'staff'
  },
  createdAt: {
    type: Date,
    default: Date.now
  }
});

module.exports = mongoose.model('User', userSchema);