Lexicon: Poll, Poll Answer

[keaysma]

Summary

This is a set of 3 lexicons that are designed to allow the creation of, and interaction with polls, as part of the bsky lexicon family. Conceptually there are two parts of a poll:

• The actual Poll: This is not defined as an independent record, but an embedded part of a Post record. A poll simply contains a question as well as a set of answers, and is represented as a JSON object. As posts are non-editable, polls are then also non-editable.
• A Poll Answer: This is an independent record, which references a Post, in which a Poll is embedded. A Poll Answer contains an answer field, which is a single numerical value. The answer field is intended to be used with a bit mask to determine which answer OR answers an actor has selected in a poll. This sets-up the ability to allow both single-answer, as well as multi-answer polls. As independent records, it is intended that an actor could edit their own poll answer in the future.

Notes/Attribution

Based on discussion: #1310

This is PR strictly contains lexicon definitions cherry-picked from #3248. That PR contains codegen and other work, too much for an initial review. I will be keeping that PR for reference.