Implement "Add to favorites" option for GIF messages

[briansztamfater]

Feature Issue

This is blocked until we have support for GIF messages

User Story

As a user, I want to add a GIF from a GIF message to favorites so that I can find it easily the next time

Description

Flow TBD

Acceptance Criteria

TBD

Notes

Link to Message Context Drawer in Figma: https://www.figma.com/file/PPWkgOYlZZDxZv5SDGsZVV/Posts-%26-Attachments?node-id=4388%3A633149