feat: add password login

server/src/models/user.js

@@ -1,9 +1,17 @@
 import { model } from 'mongoose'
 
 const User = model('User', {
-  username: String,
-  password: String,
-  email: String,
+  username: {
+    type: String,
+    unique: true,
+    required: true,
+  },
+  email: {
+    type: String,
+    unique: true,
+    required: true,
+  },
+  hashedPassword: String,
 })
 
 export default User