feat(web): add Next.js portfolio with live MT5 dashboard

- Linear design system (dark canvas, lavender accent)
- Live account stats, open positions, pending orders (30s polling)
- Trade history with equity curve chart
- Backtest results table
- Proxy API routes — MT5_BASE_URL server-side only, never exposed to browser
- Deploy on Vercel: set MT5_BASE_URL env var

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

web/components/PositionsTable.tsx

@@ -0,0 +1,42 @@
+import type { Position } from "@/lib/mt5";
+import { formatCurrency } from "@/lib/format";
+
+export default function PositionsTable({ positions, currency = "USD" }: {
+  positions: Position[];
+  currency?: string;
+}) {
+  return (
+    <table className="data-table">
+      <thead>
+        <tr>
+          {["Symbol", "Side", "Volume", "Entry", "Current", "SL", "TP", "P&L"].map(h => (
+            <th key={h}>{h}</th>
+          ))}
+        </tr>
+      </thead>
+      <tbody>
+        {positions.map((p) => {
+          const isBuy = p.type === 0;
+          return (
+            <tr key={p.ticket}>
+              <td className="font-mono font-medium text-ink">{p.symbol}</td>
+              <td>
+                <span className={`status-pill ${isBuy ? "status-bull" : "status-bear"}`}>
+                  {isBuy ? "BUY" : "SELL"}
+                </span>
+              </td>
+              <td className="font-mono text-ink-md">{p.volume}</td>
+              <td className="font-mono text-ink-md">{p.price_open.toFixed(2)}</td>
+              <td className="font-mono text-ink-md">{p.price_current.toFixed(2)}</td>
+              <td className="font-mono text-ink-sub">{p.sl > 0 ? p.sl.toFixed(2) : "—"}</td>
+              <td className="font-mono text-ink-sub">{p.tp > 0 ? p.tp.toFixed(2) : "—"}</td>
+              <td className={`font-mono font-semibold ${p.profit >= 0 ? "text-bull" : "text-bear"}`}>
+                {formatCurrency(p.profit, currency)}
+              </td>
+            </tr>
+          );
+        })}
+      </tbody>
+    </table>
+  );
+}