refacto: Changing some docker images to hardened non-root ones + README update

server/app.js

@@ -1,4 +1,5 @@
 import express from "express";
+import cors from "cors";
 import path from "path";
 import { fileURLToPath } from "url";
 import authRouter from "./routes/auth.js";
@@ -8,6 +9,7 @@ const __dirname = path.dirname(fileURLToPath(import.meta.url));
 const publicDir = path.join(__dirname, "..", "public");
 
 const app = express();
+app.use(cors({ origin: process.env.CORS_ORIGIN ?? "*" }));
 app.use(express.json());
 app.use(express.static(publicDir));