[lib] Replace LegacyThreadInfo with ThreadInfo where simple

Summary:
Went through and swapped LegacyThreadInfo with ThreadInfo where it was simple. Will need to go through web and native and update some of the "leaf components" to make further updates.

Depends on D10125

Test Plan: CI/flow/etc

Reviewers: ashoat, ginsu, tomek, rohan

Reviewed By: ashoat

Differential Revision: https://phab.comm.dev/D10126