feat(api): update API configuration and add proxy rewrites

- Remove the NEXT_PUBLIC_API_URL from the production environment file.
- Change axios base URL to use a local proxy endpoint.
- Add rewrites in next.config.mjs to route API requests through the proxy.

src/lib/api/axios.ts

@@ -9,7 +9,7 @@ import {
 import axios from "axios";
 
 const api = axios.create({
-  baseURL: process.env.NEXT_PUBLIC_API_URL,
+  baseURL: "/api/proxy/",
   timeout: 10000,
   headers: {
     "Content-Type": "application/json",