[web] split the inline engagement pill into two
Summary:
As a first step to redesigning the InlineEngagement component we should split the sidebar and the reactions into two separate pills.
This diff and subsequent diffs won't be landed until the rest of the web inline engagement work is completed
Depends on D8677
Test Plan:
Please look at the screenshots below:
Before:
After:
Reviewers: atul, kamil
Reviewed By: atul
Subscribers: ashoat, tomek
Differential Revision: https://phab.comm.dev/D8678