[web] Expose messages fetching function through the worker and sqlite-api

Summary:
We also need to call this function on web.

https://linear.app/comm/issue/ENG-8701/create-c-functions-that-fetch-a-subset-of-messages

Depends on D13141

Test Plan: Tested this later in the stack by checking if fetching messages from the DB works on the web, in thick threads with a lot of messages.

Reviewers: kamil, inka

Reviewed By: kamil

Subscribers: ashoat

Differential Revision: https://phab.comm.dev/D13142