[native] Remove renderSearch in ChatThreadList and inline ChatThreadListSearch directly

Summary:
Instead of passing a function to create ChatThreadListSearch we can inline the component directly.

As part of this we also replace additionalProps w/ more precise innerSearchAutoFocus and innerSearchActive props.

Depends on D9207

Test Plan: Search experience continues to look and work as expected. Set logs in all expected callbacks to ensure that they fired as expected. Made sure that x-icon and "Cancel" button continue to look and behave as before.

Reviewers: ginsu, tomek, rohan

Reviewed By: tomek

Subscribers: ashoat

Differential Revision: https://phab.comm.dev/D9208