async function submitWithRetry(jobData, maxRetries = 5) {
  for (let attempt = 0; attempt < maxRetries; attempt++) {
    const response = await fetch("https://api.muvi.video/v1/jobs/submit", {
      method: "POST",
      headers: {
        "Authorization": "Bearer YOUR_API_KEY",
        "Content-Type": "application/json"
      },
      body: JSON.stringify(jobData)
    });

    if (response.ok) {
      return await response.json();
    }

    const error = await response.json();

    // Non-retryable errors
    if (response.status >= 400 && response.status < 500 && response.status !== 429) {
      throw new Error(`${error.error.code}: ${error.error.message}`);
    }

    // Rate limited — respect retryAfter
    if (response.status === 429) {
      const retryAfter = error.error.details?.retryAfter || 30;
      await new Promise(r => setTimeout(r, retryAfter * 1000));
      continue;
    }

    // Server error — exponential backoff
    const delay = Math.min(1000 * Math.pow(2, attempt), 60000);
    await new Promise(r => setTimeout(r, delay));
  }

  throw new Error("Max retries exceeded");
}