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/lib/format.ts

@@ -0,0 +1,22 @@
+export function formatCurrency(n: number, currency = "USD"): string {
+  return new Intl.NumberFormat("en-US", {
+    style: "currency", currency,
+    minimumFractionDigits: 2,
+    maximumFractionDigits: 2,
+  }).format(n);
+}
+
+export function formatPct(n: number, decimals = 1): string {
+  return `${n >= 0 ? "+" : ""}${n.toFixed(decimals)}%`;
+}
+
+export function formatDate(iso: string): string {
+  return new Date(iso).toLocaleString("en-US", {
+    month: "short", day: "numeric",
+    hour: "2-digit", minute: "2-digit",
+  });
+}
+
+export function formatPrice(n: number, digits = 2): string {
+  return n.toFixed(digits);
+}

web/lib/mt5.ts

@@ -0,0 +1,102 @@
+// Server-side only — bridge URL never leaves this file
+
+async function apiFetch<T>(path: string): Promise<T> {
+  const base = process.env.MT5_BASE_URL ?? "http://localhost:8000";
+  const res = await fetch(`${base}${path}`, {
+    next: { revalidate: 0 }, // always fresh
+  });
+  if (!res.ok) throw new Error(`MT5 bridge ${path} → ${res.status}`);
+  return res.json();
+}
+
+// ── Types ────────────────────────────────────────────────────────────────────
+
+export interface AccountInfo {
+  login: number;
+  balance: number;
+  equity: number;
+  profit: number;
+  margin: number;
+  margin_free: number;
+  margin_level: number;
+  currency: string;
+  leverage: number;
+  name: string;
+  server: string;
+}
+
+export interface Position {
+  ticket: number;
+  symbol: string;
+  type: number; // 0=buy, 1=sell
+  volume: number;
+  price_open: number;
+  price_current: number;
+  sl: number;
+  tp: number;
+  profit: number;
+  swap: number;
+  comment: string;
+  magic: number;
+  time: string;
+}
+
+export interface PendingOrder {
+  ticket: number;
+  symbol: string;
+  type: number; // 2=BUY_LIMIT, 3=SELL_LIMIT, 4=BUY_STOP, 5=SELL_STOP
+  volume_initial: number;
+  volume_current: number;
+  price_open: number;
+  price_current: number;
+  sl: number;
+  tp: number;
+  magic: number;
+  comment: string;
+  time_setup: string;
+}
+
+export interface Deal {
+  ticket: number;
+  order: number;
+  time: string;
+  type: number; // 0=buy, 1=sell, 2=balance
+  entry: number; // 0=in, 1=out
+  symbol: string;
+  volume: number;
+  price: number;
+  commission: number;
+  swap: number;
+  profit: number;
+  comment: string;
+  magic: number;
+}
+
+// ── Wrappers ──────────────────────────────────────────────────────────────────
+
+interface DataVec<T> { data: T[]; count: number }
+
+export async function getAccount(): Promise<AccountInfo> {
+  const w = await apiFetch<DataVec<AccountInfo>>("/account");
+  const item = w.data[0];
+  if (!item) throw new Error("empty /account response");
+  return item;
+}
+
+export async function getPositions(): Promise<Position[]> {
+  const w = await apiFetch<DataVec<Position>>("/positions");
+  return w.data;
+}
+
+export async function getOrders(symbol?: string): Promise<PendingOrder[]> {
+  const path = symbol ? `/orders?symbol=${encodeURIComponent(symbol)}` : "/orders";
+  const w = await apiFetch<DataVec<PendingOrder>>(path);
+  return w.data;
+}
+
+export async function getDeals(dateFrom: string, dateTo: string, symbol?: string): Promise<Deal[]> {
+  let path = `/history/deals?date_from=${encodeURIComponent(dateFrom)}&date_to=${encodeURIComponent(dateTo)}`;
+  if (symbol) path += `&symbol=${encodeURIComponent(symbol)}`;
+  const w = await apiFetch<DataVec<Deal>>(path);
+  return w.data;
+}