Adds a new integration for Resend, an email sending service.
Includes:
- Resend API credential (`ResendApi.credentials.ts`) for API key authentication.
- Resend action node (`nodes/Resend/Resend.node.ts`):
- Supports "Send Email" operation with parameters for to, from, subject, html, text, cc, bcc, reply_to, and tags.
- Uses Resend API `https://api.resend.com/emails`.
- Resend trigger node (`nodes/Resend/ResendTrigger.node.ts`):
- Handles Resend webhooks for various event types (email.sent, email.delivered, etc.).
- Implements webhook signature verification using Svix and a user-provided signing secret.
- Allows you to select which events to listen for.
- Official Resend SVG icon (`nodes/Resend/Resend.svg`).
- Adds `svix` as a dependency for webhook verification.
Replace the docs URL. We need to be clear that the URL must point to their site. The automatic linking won't work as obviously we won't have official docs for community nodes.