feat(inventory): add origin field to InventoryItem and update related DTOs and services

frontend/app/api/products/pending/route.ts

@@ -0,0 +1,16 @@
+import { NextRequest, NextResponse } from 'next/server';
+import { getAuthHeaders } from '../../../../lib/auth-headers';
+
+const API_BASE = process.env.NEXT_PUBLIC_API_URL_INTERNAL || 'http://recipe-api:8080';
+
+export async function POST(req: NextRequest) {
+  const body = await req.json();
+  const authHeaders = await getAuthHeaders();
+  const res = await fetch(`${API_BASE}/api/products/pending`, {
+    method: 'POST',
+    headers: { 'Content-Type': 'application/json', ...authHeaders },
+    body: JSON.stringify(body),
+  });
+  const data = await res.json();
+  return NextResponse.json(data, { status: res.status });
+}