Initial working version, positions show.

frontend/app.js

@@ -0,0 +1,32 @@
+// Minimal vanilla-JS frontend to poll only positions and render the positions table
+const qs = (s) => document.querySelector(s);
+const ptbody = qs('#positions-table tbody');
+
+async function fetchJson(path) {
+  const res = await fetch(path);
+  if (!res.ok) throw new Error('Network response not ok');
+  return res.json();
+}
+
+function renderPositions(list) {
+  ptbody.innerHTML = '';
+  for (const p of list) {
+    const row = document.createElement('tr');
+    const avg = p.averageCost ?? p.average_cost ?? '';
+    row.innerHTML = `<td>${p.symbol}</td><td>${p.position}</td><td>${avg}</td><td>${p.account ?? ''}</td>`;
+    ptbody.appendChild(row);
+  }
+}
+
+async function pollPositions() {
+  try {
+    const positions = await fetchJson('/api/positions');
+    renderPositions(positions);
+  } catch (e) {
+    console.warn('Positions polling error', e);
+  }
+}
+
+// start polling every 2 seconds
+pollPositions();
+setInterval(pollPositions, 2000);