[lib] generate message store ops for threads after creating local message

Summary:
This code generates operations needed for updating threads part of message store after creating local message.

Depends on D7418

Test Plan: Try to send message some media messages nad check is there are no errors in console.

Reviewers: tomek, marcin

Reviewed By: tomek

Subscribers: ashoat, atul

Differential Revision: https://phab.comm.dev/D7419