[lib] Add functions for getting cached results from ENSCache
Summary: This will allow us to show the right ENS name from hooks right away, instead of flashing in the wrong name and then rerendering with the right name immediately after.
Test Plan:
- New unit tests
- Tested in combination with the following diff
Reviewers: atul
Reviewed By: atul
Subscribers: tomek
Differential Revision: https://phab.comm.dev/D6418