🚀 Fix: Chat connectivity using absolute backend URL

frontend/components/AgentChat.tsx

@@ -2,7 +2,7 @@
 
 import { useState, useRef, useEffect } from "react";
 import type { Tender, CompanyProfile } from "../lib/types";
-import { uploadDocument } from "../lib/api";
+import { uploadDocument, getAPIBase } from "../lib/api";
 
 type Message = {
   role: "user" | "assistant";
@@ -113,7 +113,7 @@ export default function AgentChat({ tender, companyProfile }: Props) {
     setIsLoading(true);
 
     try {
-      const response = await fetch("/api/chat", {
+      const response = await fetch(`${getAPIBase()}/api/chat`, {
         method: "POST",
         headers: { "Content-Type": "application/json" },
         body: JSON.stringify({