Netlify Scheduled Functions Transactional Email with Rovela (2026): Cron Config + Idempotency-Key per Window
Run a Netlify Scheduled Function on a UTC cron (inline config or netlify.toml), load ROVELA_API_KEY from Functions-scoped secrets, and POST /emails with Idempotency-Key scoped to the schedule window. Distinct from Fly Machines, Render Cron, Railway cron, Vercel HTTP cron, and GitHub Actions.