[native] introduce MessageReactionsModal
Summary:
introduce MessageReactionsModal. MessageReactionsModal shows all the users who have reacted to a message, what their username is and what reaction they used. I decided to punt the implementation of the filter buttons at the top of the design since every message will be a like for the moment
Depends on D6348
Linear Task: ENG-2719
Test Plan:
Please watch the demo video to see how MessageReactionsModal works
Reviewers: atul, tomek
Reviewed By: atul
Subscribers: ashoat, tomek, atul
Differential Revision: https://phab.comm.dev/D6350