「要求ヘッダー」
  Accept: */*
  Accept-Encoding: gzip, br, zstd, deflate
  Content-Length: 0
  Content-Type: 
  Host: req.fast-email.link
  User-Agent: Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; ClaudeBot/1.0; +claudebot@anthropic.com)
  Via: 2.0 Caddy
  X-Forwarded-For: 216.73.216.51
  X-Forwarded-Host: req.fast-email.link
  X-Forwarded-Proto: https