We need to be able to differentiate mutliple different cases for the Talk integration:
- If user A was added to a circle by user B in the contacts app => user B
- If user A was added to a circle via CLI => null/cli
- If user A was invited to a circle by user B and user A accepts the invite => user B
- If user A was invited to a circle via CLI and user A accepts the invite => null/cli
- If user A joins a public circle => user A
- If user A requests to join a circle and user B approved => user B
- If user A requests to join a circle and it is approved via CLI => null/cli