Подсказки текстовые с городами должны быть, когда ты вводишь название города, чтобы избежать неправильного написания. Вот этот скрипт:

document.addEventListener('DOMContentLoaded', function() {
const cities = <%= JSON.stringify(citiesAndRegions.map(item => item.city)) %>;


$("#city").autocomplete({
source: cities,
minLength: 1,
});

const city = document.querySelector("#city").value;
const url = "/search?query=" + encodeURIComponent(query) +
"&role=" + encodeURIComponent(role) +
"&city=" + encodeURIComponent(city);
});

не работает. Все должно работать так, как будто это Facebook или VK - ты пишешь название, тебе предлагается правильное (стандартизированное) название города из russia.json и ты выбираешь его. 

вот так выглядит структура russia.json:
[
  {
    "region": "Москва и Московская обл.",
    "city": "Москва"
  },
  {
    "region": "Москва и Московская обл.",
    "city": "Абрамцево"
  },

app.js:
const express = require("express");
const fs = require("fs");
const session = require("express-session");
const fileUpload = require("express-fileupload");
const app = express();
const fuzzball = require("fuzzball");

app.set("view engine", "ejs");
app.use(express.static("public"));
app.use(express.urlencoded({ extended: true }));
app.use(fileUpload());
app.use(session({
  secret: "mysecretkey",
  resave: false,
  saveUninitialized: false
}));






const citiesAndRegions = JSON.parse(fs.readFileSync("./db/russia.json"));

const predefinedGenres = ['Rock', 'Pop', 'Jazz', 'Hip Hop', 'Electronic', 'Blues'];

function getMusicianById(id) {
  const data = fs.readFileSync("./db/musicians.json");
  const musicians = JSON.parse(data);

  return musicians.musicians.find(musician => musician.id === id);
}

function requireLogin(req, res, next) {
  if (req.session.musicianId) {
    next();
  } else {
    res.redirect("/login");
  }
}

function search(query = '', role = '', city = '') {
  const data = fs.readFileSync('./db/musicians.json');
  const musicians = JSON.parse(data).musicians.map(musician => {
    return {
      name: musician.name,
      genre: musician.genre,
      originalName: musician.name,
      profileLink: `/profile/${musician.id}`,
      thumbnail: musician.thumbnail,
      soundcloud: musician.soundcloud,
      role: musician.role,
	  city: musician.city
      
    };
  });

  let results = [];

  if (query || role || city) {
    const lowerQuery = query.toLowerCase();
    results = musicians.filter(musician => {
      const nameScore = musician.name.toLowerCase().startsWith(lowerQuery) ? 2 : musician.name.toLowerCase().includes(lowerQuery) ? 1 : 0;
      const genreScore = musician.genre.toLowerCase().startsWith(lowerQuery) ? 2 : musician.genre.toLowerCase().includes(lowerQuery) ? 1 : 0;
      
     return (
    nameScore + genreScore > 0 &&
    (role === "" || musician.role === role) &&
	(city === "" || (musician.city && musician.city.toLowerCase().trim() === city.toLowerCase().trim()))
    //(city === "" || musician.city.toLowerCase() === city.toLowerCase())
  );

    }).sort((a, b) => {
      const aNameScore = a.name.toLowerCase().startsWith(lowerQuery) ? 2 : a.name.toLowerCase().includes(lowerQuery) ? 1 : 0;
      const bNameScore = b.name.toLowerCase().startsWith(lowerQuery) ? 2 : b.name.toLowerCase().includes(lowerQuery) ? 1 : 0;
      const aGenreScore = a.genre.toLowerCase().startsWith(lowerQuery) ? 2 : a.genre.toLowerCase().includes(lowerQuery) ? 1 : 0;
      const bGenreScore = b.genre.toLowerCase().startsWith(lowerQuery) ? 2 : b.genre.toLowerCase().includes(lowerQuery) ? 1 : 0;

      // Sort by name score, then genre score, then location score (descending)
      if (aNameScore + aGenreScore + a.location < bNameScore + bGenreScore + b.location) {
        return 1;
      } else if (aNameScore + aGenreScore + a.location > bNameScore + bGenreScore + b.location) {
        return -1;
      } else {
        return 0;
      }
    });

    // Remove duplicates
    results = results.filter((result, index, self) =>
      index === self.findIndex(r => (
        r.name === result.name && r.genre === result.genre && r.city === result.city
      ))
    );
  }

  return results;
}

app.use((req, res, next) => {
  if (req.session.musicianId) {
    const musician = getMusicianById(req.session.musicianId);
    res.locals.musician = musician;
    res.locals.userLoggedIn = true;
    res.locals.username = musician.name;
  } else {
    res.locals.userLoggedIn = false;
  }

  next();
});

app.get("/", (req, res) => {
  const data = fs.readFileSync("./db/musicians.json");
  const musicians = JSON.parse(data);

  res.render("index", { musicians: musicians.musicians });
});

app.get("/register", (req, res) => {
  if (req.session.musicianId) {
    const musician = getMusicianById(req.session.musicianId);
    res.redirect("/profile/" + musician.id);
  } else {
	  
	  
	  
    res.render("register", { citiesAndRegions, city:'' });
  }
});

app.post("/register", (req, res) => {
  if (req.session.musicianId) {
    const musician = getMusicianById(req.session.musicianId);
    res.redirect("/profile/" + musician.id);
  } else {
    const data = fs.readFileSync("./db/musicians.json");
    const musicians = JSON.parse(data);

    const newMusician = {
      id: musicians.musicians.length + 1,
      name: req.body.name,
      genre: req.body.genre,
      instrument: req.body.instrument,
      soundcloud: req.body.soundcloud,
      password: req.body.password,
	  role: req.body.role,
	  city: req.body.city,
      login: req.body.login
    };
	
	


    if (req.files && req.files.thumbnail) {
      const file = req.files.thumbnail;
      const filename = "musician_" + newMusician.id + "_" + file.name;
      file.mv("./public/img/" + filename);

      newMusician.thumbnail = filename;
    }
	
	const found = citiesAndRegions.find(
  ({ city }) => city === req.body.city.toLowerCase()
);

// Если найдено - сохраняем город и регион, если нет - оставляем только город
if (found) {
  newMusician.city = found.city;
  newMusician.region = found.region;
} else {
  newMusician.city = req.body.city;
  newMusician.region = "";
}

    musicians.musicians.push(newMusician);
    fs.writeFileSync("./db/musicians.json", JSON.stringify(musicians));

    req.session.musicianId = newMusician.id;
    res.redirect("/profile/" + newMusician.id);
  }
});

app.get("/profile/:id", (req, res) => {
  const musician = getMusicianById(parseInt(req.params.id));

  if (musician) {
    res.render("profile", { musician: musician });
  } else {
    res.status(404).send("Musician not found");
  }
});

app.get("/login", (req, res) => {
  res.render("login");
});

app.post("/login", (req, res) => {
  const data = fs.readFileSync("./db/musicians.json");
  const musicians = JSON.parse(data);

  const musician = musicians.musicians.find(musician => musician.login === req.body.login && musician.password === req.body.password);

  if (musician) {
    req.session.musicianId = musician.id;
    res.redirect("/profile/" + musician.id);

  } else {
    res.render("login", { error: "Invalid login or password" });
  }
});

app.get("/logout", (req, res) => {
  req.session.destroy();
  res.redirect("/");
});

app.get('/search', (req, res) => {
  const query = req.query.query || '';
  const role = req.query.role || '';
  const city = req.query.city || '';
  let musicians = [];

  if (query || role || city) {
    musicians = search(query, role, city);
  } else {
    const data = fs.readFileSync('./db/musicians.json');
    musicians = JSON.parse(data).musicians.map(musician => {
      return {
        name: musician.name,
        genre: musician.genre,
        originalName: musician.name,
        profileLink: `/profile/${musician.id}`,
        thumbnail: musician.thumbnail,
        soundcloud: musician.soundcloud,
        role: musician.role,
		city: musician.city
      };
    });
  }

  res.locals.predefinedGenres = predefinedGenres;
  res.render('search', { musicians, query, role, city, citiesAndRegions });

  //res.redirect('/search');
});

app.get("/profile/:id/edit", requireLogin, (req, res) => {
  const musician = getMusicianById(parseInt(req.params.id));

  if (musician) {
    if (req.session.musicianId === musician.id) { // Check if the logged-in user is the owner of the profile
      res.render("edit-profile", { musician: musician });
    } else {
      res.status(403).send("Access denied");
    }
  } else {
    res.status(404).send("Musician not found");
  }
});





app.post('/profile/:id/edit', requireLogin, (req, res) => {
  const musician = getMusicianById(parseInt(req.params.id));

  if (musician) {
    if (!req.body.name || !req.body.genre) {
      res.status(400).send('Please fill out all fields');
    
    } else {
      musician.name = req.body.name;
      musician.genre = req.body.genre;
      musician.instrument = req.body.instrument;
      musician.soundcloud = req.body.soundcloud;
	  musician.soundcloud1 = req.body.soundcloud1;
  musician.soundcloud2 = req.body.soundcloud2;
      musician.location = req.body.location;
	  musician.role = req.body.role;
      musician.bio = req.body.bio;

      if (req.files && req.files.thumbnail) {
        const file = req.files.thumbnail;
        const filename = 'musician_' + musician.id + '_' + file.name;
        file.mv('./public/img/' + filename);
        musician.thumbnail = filename;
      }

      const data = fs.readFileSync('./db/musicians.json');
      const musicians = JSON.parse(data);
      const index = musicians.musicians.findIndex(m => m.id === musician.id);
      musicians.musicians[index] = musician;

      fs.writeFileSync('./db/musicians.json', JSON.stringify(musicians));

      res.redirect('/profile/' + musician.id);
    }
  } else {
    res.status(404).send('Musician not found');
  }
  
  
});

function isValidSoundCloudUrl(url) {
  return url.startsWith('https://soundcloud.com/');
}

app.listen(3000, () => {
  console.log("Server started on port 3000");
});

search.ejs:

<!DOCTYPE html>
<html>
<head>
	<title>Search Musicians</title>
	<link rel="stylesheet" href="/node_modules/jquery-ui/themes/base/all.css" />
<script src="/node_modules/jquery/dist/jquery.min.js"></script>
<script src="/node_modules/jquery-ui-dist/jquery-ui.min.js"></script>
</head>
<body>
	<h1>Search Musicians</h1>
	<form action="/search" method="get">
		<label for="query">Search by name or genre:</label> <input id="query" name="query" type="text" value="<%= query %>"><br>
		<br>
		<label for="role">Search by role:</label> <select id="role" name="role">
			<option value="">
				All
			</option>
			<option value="Band">
				Band
			</option>
			<option value="Artist">
				Artist
			</option>
		</select>
		<% if (musicians.length > 0) { %>
<label for="city">Search by location:</label>
<input id="city" name="city" type="text" value="<%= city %>">
<% } %>
		<br>
		<!-- Add new input field for location -->


		<br>
		
		<br>
		<button type="submit">Search</button>
	</form><%if (musicians.length > 0) { %>
	<h2>Results:</h2>
	<ul>
		<%musicians.forEach(musician => { %>
		<li>
			<a href="<%= musician.profileLink %>"><%= musician.name %> <%if (musician.thumbnail) { %> <img src="/img/<%= musician.thumbnail %>" alt="<%= musician.name %>"> <%} %></a> - <%= musician.genre %> - <%= musician.location %> <%if (musician.soundcloud) { %> <a href="%3C%=%20musician.soundcloud%20%%3E">SoundCloud</a> <%} %>
		</li><%}); %>
	</ul><%} else if (query || role) { %>
	<p>No musicians found.</p><%} %>
	<!-- <script>
  (function () {
    const cities = <%= JSON.stringify(citiesAndRegions.map(item => item.city)) %>;


("#city").autocomplete({
      source: cities,
      minLength: 1,
    });
  });
</script> -->
<script>
document.addEventListener('DOMContentLoaded', function() {
const cities = <%= JSON.stringify(citiesAndRegions.map(item => item.city)) %>;


$("#city").autocomplete({
source: cities,
minLength: 1,
});

const city = document.querySelector("#city").value;
const url = "/search?query=" + encodeURIComponent(query) +
"&role=" + encodeURIComponent(role) +
"&city=" + encodeURIComponent(city);
});
</script>
</body>
</html>



Так же проблема поиска в том, что ищет только по полному совпадению названия города, анпример, написание "Санкт" не допускается, если только введу "Санкт-Петербург"