[native][web] Add a method fetching messages by ID
Summary:
This allows retrying messages generated by a single action.
https://linear.app/comm/issue/ENG-8675/add-option-to-manually-retry-a-message
Depends on D12743
Test Plan: Tested in combination with the rest of the stack. Sending messages requires calling this API so checking if messages are sent tests it.
Reviewers: kamil, marcin
Reviewed By: kamil
Subscribers: ashoat
Differential Revision: https://phab.comm.dev/D12744