[Redesign] Rebuild Chatlog

Summary: Ref T8099. I use this app daily, so 30 minutes of love is good enough for me.

Test Plan:
Tested with a fake chat.

{F443522}

Reviewers: btrahan, epriestley

Reviewed By: epriestley

Subscribers: Korvin, epriestley

Maniphest Tasks: T8099

Differential Revision: https://secure.phabricator.com/D13046