// ── API Calls ──

async function apiChat(model, messages, systemPrompt) {
  return fetch('/api/chat', {
    method: 'POST',
    headers: { 'Content-Type': 'application/json' },
    body: JSON.stringify({ model, messages, systemPrompt })
  });
}

async function apiHistory(sessionId = 'null', limit = 50) {
  const resp = await fetch(`/api/history?sessionId=${sessionId}&limit=${limit}`);
  return resp.json();
}