Support looking up a user by a provided JID

[nesium]

Required here.

• Provide a core-client method to fetch any JID's name (which might not be in our current roster; could also be the whole profile but I only need the name and avatar), will be bound here: prose-im/prose-app-web@6e1778c#diff-caf3f31c46b80297206df2237259045d7a6d03e934f72a92958d2964b87fe63fR200
• Provide a core-client method to add a JID + name pair to the user's roster, will be bound here: prose-im/prose-app-web@6e1778c#diff-ed5b04fbb5038210f200e7a33778e38b74d3d9e1eb16b2b68f2a43f1b51e0379R343

[nesium]

It seems that this could be done via a search defined in XEP-0055. If you know anything else let me know @valeriansaliou

[valeriansaliou]

It seems that this could be done via a search defined in XEP-0055. If you know anything else let me know @valeriansaliou

I don't know any other way to do it at the moment, we can go for this XEP. At least that's also the one I was using after disco#items in Jappix back in the times to allow searching in the server's user list, ref. https://github.com/jappix/jappix/blob/master/app/javascripts/dataform.js#L33 (via the NS_SEARCH constant)

Server support for this is excellent.