[lib][native] Displaying edited messages from database

Summary:
Now edited messages are visible in the chats. Currently, it's only possible to edit the message (send a new message with edit_message type) from the database. Editing message
which is source of sidebar currently isn't visible in the sidebar view.

Test Plan:

• added edited message to the database, checked if it shows correctly,
• edited several times the same message, checked if the latest one is shown,
• edited a few messages in one thread, checked if the messages are updated correctly,
• edited a few messages in a few threads, checked if the messages are correctly updated

Reviewers: michal, inka, ginsu

Reviewed By: michal, ginsu

Subscribers: ashoat, tomek, atul

Differential Revision: https://phab.comm.dev/D6965