collectMissingPreviewFiles = async (previewFiles, storageDir) => {
  const missingFiles = []

  const t0 = Date.now()
  for (let file of previewFiles) {
    const missing = await access(path.resolve(storageDir, file)).then(() => false, () => true)
    if (missing) {
      missingFiles.push(file)
    }
  }
  log.trace(t0, `Found ${missingFiles.length} missing from total ${previewFiles.length} remote preview files`)

  return missingFiles
}
@param {string[]} previewFiles
@param {string} storageDir
@returns {Promise<string[]>}