OpenTofu support and Go SDK

Having an official Terraform/OpenTofu provider for Mailtrap to manage resources in a consistent, repeatable way using IaC.

Given OpenTofu’s role as the open-source alternative to Terraform, compatibility with it would be important for long-term adoption.

An official Go SDK covering the Email API, SMTP, and Sandbox would not only improve the developer experience for Go users but would also serve as a strong foundation for building and maintaining an IaC provider.