add json placeholder link for test

app/json-placeholder/[id]/route.ts

@@ -0,0 +1,18 @@
+import { NextRequest, NextResponse } from "next/server";
+
+export async function GET(
+  request: NextRequest,
+  { params: { id } }: { params: { id: string } },
+) {
+  if (!id) throw new Error("Where is id...");
+
+  const res = await fetch(`https://jsonplaceholder.typicode.com/todos/${id}`);
+
+  if (!res.ok) {
+    return new NextResponse("{}");
+  }
+
+  const body = await res.json();
+
+  return new NextResponse(JSON.stringify(body, null, 2));
+}