add core functionalities

Author: iChristwin

.gitignore

@@ -128,3 +128,4 @@ dist
 .yarn/build-state.yml
 .yarn/install-state.gz
 .pnp.*
+cache/

index.js

@@ -0,0 +1,16 @@
+import "dotenv/config";
+import { handleUplinks } from "./src/mqtt";
+import express, { Express, Request, Response } from "express";
+
+const app: Express = express();
+const port = process.env.PORT || 3000;
+
+handleUplinks();
+
+app.get("/", (req: Request, res: Response) => {
+  res.send("Express + TypeScript Server");
+});
+
+app.listen(port, () => {
+  console.log(`[server]: Server is running at http://localhost:${port}`);
+});