woof. killed useClient and use nextjs api

app/admin/merchants/page.tsx

@@ -2,8 +2,7 @@
 
 import { useEffect, useState } from "react";
 
-const API_BASE_URL =
-  process.env.NEXT_PUBLIC_API_BASE_URL ?? "";
+// API routes now handled by Next.js /api routes (server-side)
 
 type MerchantAdminDto = {
   id: number;
@@ -91,7 +90,7 @@ export default function MerchantsAdminPage() {
         setLoading(true);
         setError(null);
 
-        const url = `${API_BASE_URL}/api/admin/merchants`;
+        const url = `/api/admin/merchants`;
         console.log("Loading merchants from:", url);
 
         const res = await fetch(url, {
@@ -150,7 +149,7 @@ export default function MerchantsAdminPage() {
       setError(null);
       setBanner(null);
 
-      const res = await fetch(`${API_BASE_URL}/api/admin/merchants/${id}`, {
+      const res = await fetch(`/api/admin/merchants/${id}`, {
         method: "PUT",
         headers: { "Content-Type": "application/json" },
         body: JSON.stringify({
@@ -189,7 +188,7 @@ export default function MerchantsAdminPage() {
       setError(null);
       setBanner(null);
 
-      const res = await fetch(`${API_BASE_URL}/api/admin/imports/${id}`, {
+      const res = await fetch(`/api/admin/merchants/${id}/import`, {
         method: "POST",
       });
 
@@ -218,7 +217,7 @@ export default function MerchantsAdminPage() {
       setBanner(null);
 
       const res = await fetch(
-        `${API_BASE_URL}/api/admin/imports/${id}/offers-only`,
+        `/api/admin/merchants/${id}/offer-sync`,
         { method: "POST" }
       );
 
@@ -247,7 +246,7 @@ export default function MerchantsAdminPage() {
       setError(null);
       setBanner(null);
 
-      const res = await fetch(`${API_BASE_URL}/api/v1/admin/merchants`, {
+      const res = await fetch(`/api/admin/merchants`, {
         method: "POST",
         headers: { "Content-Type": "application/json" },
         body: JSON.stringify({