Node type proposal: Notification #19
Description
Send notifications through multiple channels from within a workflow. Supported channels: desktop notification (Electron native), email (SMTP config or service like SendGrid), Slack (webhook URL), Discord (webhook URL), generic webhook (POST to URL). Template support for message body using workflow variables. Use cases: alert on workflow completion, notify on errors, send daily digest results. Could integrate with the existing webhook/trigger system for bidirectional communication.