[native] Add message search store

Summary: issue: ENG-8831

Test Plan: Tested with the next diff. Added an "add search message" operation on the js side and tested that updateMessageSearchIndex was run and no errors showed up in Metro nor in XCode console

Reviewers: tomek, kamil, marcin

Reviewed By: kamil

Subscribers: ashoat

Differential Revision: https://phab.comm.dev/D12795