[native] [refactor] use toggle unread hook

Summary:
Use useToggleUnreadStatus hook, remove old API call logic.

Test Plan:
Go to the simulator:

• Read and unread chat thread items.
• Make sure animations are still smooth.
• Go to web client and API call (that toggling read and unread) is still reflected on both native client and web client.

Reviewers: atul, ashoat

Reviewed By: ashoat

Subscribers: palys-swm, Adrian, karol-bisztyga

Differential Revision: https://phabricator.ashoat.com/D3419