[web][native] Show relationship prompt in thick PERSONAL threads

Summary: issue: ENG-9188

Test Plan: Tested on web and native that buttons do show up in a chat with a user the current user is not friends with. Tested they don't show up in a chat with a user the usrrent user is friends with

Reviewers: tomek, kamil

Reviewed By: tomek

Subscribers: ashoat

Differential Revision: https://phab.comm.dev/D13267