chore: add nextjs template

frontend-nextjs/app/api/products/route.ts

@@ -0,0 +1,30 @@
+import { NextResponse } from "next/server";
+import { Pool } from "pg";
+
+// Database connection - uses environment variables
+const pool = new Pool({
+  host: process.env.DB_HOST || "127.0.0.1",
+  port: parseInt(process.env.DB_PORT || "5432"),
+  user: process.env.DB_USER || "myuser",
+  password: process.env.DB_PASSWORD || "mypassword",
+  database: process.env.DB_DATABASE || "mydb",
+});
+
+export async function GET() {
+  try {
+    const result = await pool.query(`
+      SELECT id, title, price_cents, slug
+      FROM products
+      ORDER BY id
+      LIMIT 100
+    `);
+
+    return NextResponse.json(result.rows);
+  } catch (error) {
+    console.error("Error fetching products:", error);
+    return NextResponse.json(
+      { error: "Failed to fetch products" },
+      { status: 500 }
+    );
+  }
+}