Convert backend to ESM

- About 5 years overdue
- Remove eslint, use bomejs instead

backend/routes/reports.js

@@ -1,15 +1,15 @@
-const express        = require('express');
-const jwtdecode      = require('../lib/express/jwt-decode');
-const internalReport = require('../internal/report');
+import express from "express";
+import internalReport from "../internal/report.js";
+import jwtdecode from "../lib/express/jwt-decode.js";
 
-let router = express.Router({
+const router = express.Router({
 	caseSensitive: true,
-	strict:        true,
-	mergeParams:   true
+	strict: true,
+	mergeParams: true,
 });
 
 router
-	.route('/hosts')
+	.route("/hosts")
 	.options((_, res) => {
 		res.sendStatus(204);
 	})
@@ -18,12 +18,12 @@ router
 	 * GET /reports/hosts
 	 */
 	.get(jwtdecode(), (_, res, next) => {
-		internalReport.getHostsReport(res.locals.access)
+		internalReport
+			.getHostsReport(res.locals.access)
 			.then((data) => {
-				res.status(200)
-					.send(data);
+				res.status(200).send(data);
 			})
 			.catch(next);
 	});
 
-module.exports = router;
+export default router;