Add support in integration for messages with a link preview

Reading the greenapi documentation for [SendMessage ](https://green-api.com/en/docs/api/sending/SendMessage/)it is possible to send a message with a link preview. This would be useful for sending notifications from HA.

<img width="767" height="267" alt="Image" src="https://github.com/user-attachments/assets/c772850d-f0eb-43dd-8881-b2a1f9c7c38b" />

