async function sendMessage() {
    const project = document.getElementById('project').value;
    const message = document.getElementById('message').value;
    const res = await fetch('http://localhost:5000/chat', {
        method: 'POST',
        headers: {'Content-Type': 'application/json'},
        body: JSON.stringify({project, message})
    });
    const data = await res.json();
    const messagesDiv = document.getElementById('messages');
    messagesDiv.innerHTML += `<p><b>Du:</b> ${message}</p><p><b>LLM:</b> ${data.reply}</p>`;
}