Save and load answers

Right now, a teams answers are not saved until the "Record All Answers" button is pressed. This is reasonable for saving scores to the leaderboard, but it would be nice to save all answers immediately to some intermediate location in case of technical difficulties requiring either the page to be reloaded or the continuation of the quiz on a different device, or something else.

Along with this, it would be nice, in general, for a teams previous answers to be automatically loaded when they're selected, and if starting from scratch is what's desired, then the "bulk options" buttons can be used.

Start by tracing the flow behind the "Record All Answers" button, team selection, and the bulk options buttons. Determine where the current team answers exist during a quiz and how they could persist across reloads or devices. Done means answers are saved before recording scores and automatically restored when a team is selected, while the bulk options can still start from scratch.

Written by the indexing model from the issue text.