protected function loadTokenFromFile($filename)
{
if (strpos($filename, '/') !== 0 && strpos($filename, '\\') !== 0) {
$filename = $this->config->getUserConfigDir() . '/' . $filename;
}
$content = file_get_contents($filename);
if ($content === false) {
throw new \RuntimeException('Failed to read file: ' . $filename);
}
return trim($content);
}