Add email verification status / network origin to profile

[Bossett]

Is your feature request related to a problem? Please describe.

There is an issue with accounts purpose-built for harassment, and while we can get somewhere with labelling hiding/etc. effective labelling has a lot of collateral damage (i.e. people are simply blocking all new accounts - which is absolutely toxic to adoption).

A couple of small (and privacy-preserving) additions could help immensely.

Describe the solution you'd like

1. Some indicator in the profile record indicating if/how an account was verified (captcha, email, etc.), this would allow an 'unverified new account' label
2. Some indicator of where an account is from - which could be a hash of the first 2 octets/4 hextets of an IP, allowing an approximate 'netblock'-type label (this could be further salted with something like unix_time/600000 so that the same netblocks would get a diff hash every ~week - which would also prevent side-effects from re-used dynamic IPs months later)

I'm envisioning this as an optional attribute on the detailed profile record from the appview, and retrievable from the PDS, something like:

"verification": {
  "emailVerified": true,
  "sourceNetwork": "dd4a5738d3733c1322dd32ae7fdf477a"
}

This would be great as additional information in ozone, and extensible in the future to allow 'per net' labelling. sourceNetwork in this example could also be used to rate-limit signups - esp. where an account has been suspended. Another case I would want to explore - add a net to a blocklist where a user on that net has a statistically significant # blocks per period.

Describe alternatives you've considered

Other alternatives (i.e. labels per the above) exist in-place, but tools are limited without a little bit more insight. The PDS can always lie here, but PDS is also public information, so a PDS found to be dishonest can be labelled.