Add Basic Auth middleware for the admin module

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

app/middlewares/basicAuth.js

+"use strict";
+
+module.exports = function basicAuth(req, res, next) {
+  var config = require(__config_path + "/config");
+  var header = req.headers.authorization || "";
+  var token = header.indexOf("Basic ") === 0 ? header.slice(6) : "";
+  var decoded = Buffer.from(token, "base64").toString("utf8");
+  var parts = decoded.split(":");
+  var user = parts[0];
+  var password = parts[1];
+
+  if (user === config.admin.user && password === config.admin.password) {
+    return next();
+  }
+
+  res.set("WWW-Authenticate", 'Basic realm="Admin"');
+  return res.status(401).send("Authentication required.");
+};