fix: add module type to package.json and remove unused import in server.js

backend/package.json

@@ -1,6 +1,7 @@
 {
   "name": "backend",
   "version": "1.0.0",
+  "type": "module",
   "main": "index.js",
   "scripts": {
     "test": "echo \"Error: no test specified\" && exit 1",

backend/server.js

@@ -9,7 +9,6 @@ import {
   removeEntries,
   saveRow,
   resetData,
-  getVitals,
 } from "./services/database.js";
 import { generateToken, authenticate } from "./services/tokenService.js";
 env.config();