[lib] Create entry store handler

Summary:
Implement the handler that processes the store ops and transforms them

Depends on D12137

https://linear.app/comm/issue/ENG-3486/move-entrystore-to-sqlite

Test Plan: Tests

Reviewers: kamil, marcin

Reviewed By: marcin

Subscribers: ashoat

Differential Revision: https://phab.comm.dev/D12141