getSticker feature

[AntonKun]

Feature Request

In the native Signal CLI, there is a method to retrieve stickers using packId and stickerId (reference: https://github.com/AsamK/signal-cli/blob/master/man/signal-cli.1.adoc#getsticker). However, this feature is currently missing in the Signal CLI REST API.

It would be fantastic if you could add support for retrieving stickers via packId and stickerId in the REST API.

Thank you for considering this request!