Add discord rich presence

[dimkauzh]

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• [X] Completed

Describe the feature

Hey, so I could you maybe add discord rich presence to Zed? Basicly discord rich presence is this thingy that shows up in your profile (see picture). You could maybe add it as a option so user can enable it if he wants or not. It would be great if it could be added, its pretty easy to implement. Thanks!

Btw sorry that the picture is in Ukrainian a little bit.

If applicable, add mockups / screenshots to help present your vision of the feature