Email Render — Supabase Edge

Supabase Edge Function (Deno) render adapter. Same API as core/email-render-next — createEmailRenderer(config?) — but reads Deno.env.get('SITE_URL'). Requires @react-email/render mapped via deno.json import map: 'npm:@react-email/render@^2.0.5'. The only place in the email subsystem that reads Deno.env.