refactor: put passport to auth folder

server/src/auth/passwordStrategy.js

@@ -0,0 +1,22 @@
+import bcrypt from 'bcrypt'
+import LocalStrategy from 'passport-local'
+import User from '../models/user.js'
+
+async function verifyPassword(username, password, done) {
+  try {
+    const user = await User.findOne({ username })
+    if (!user) {
+      return done(null, false, { message: 'Incorrect username.' })
+    }
+
+    const isPasswordValid = await bcrypt.compare(password, user.hashedPassword)
+    if (!isPasswordValid) {
+      return done(null, false, { message: 'Incorrect username or password.' })
+    }
+    return done(null, user)
+  } catch (err) {
+    return done(err)
+  }
+}
+
+export default new LocalStrategy(verifyPassword)