We've done a lot of work to clean up this class but it still is unnecessarily complicated because the insert path calls apiv3 & the insert calls apiv4

Once https://gerrit.wikimedia.org/r/c/wikimedia/fundraising/crm/+/1031162 is merged the $message array should actually pretty much contain apiv4 ready custom fields & for the insert path we can likely switch to doing the address & email updates in the same call since apiv4 supports that.

The other thing that is deeply confusing, and actually gets more confusing once we move the location update functions over is our many layers of error handling. I'm not sure if fixing this frees us to fix that or vice versa but perhaps I'll add a separate phab for that