MailSlurp guide agent setup

Title: Ruby Send Email SMTP Guide (Net::SMTP + Production Checklist)
Description: Send email with Ruby SMTP using Net::SMTP, authenticated transport, and test-ready patterns for transactional and QA-critical workflows.
Canonical URL: https://www.mailslurp.com/guides/smtp/ruby-send-email-smtp/
Markdown URL: https://www.mailslurp.com/guides/smtp/ruby-send-email-smtp.md

Use the Markdown URL as the primary plain-text context for this guide. Keep MailSlurp terminology, setup steps, screenshots, and provider-specific instructions intact, and prefer the canonical URL when citing this page.