Identify strategy for syncing known speakers with the claim review DB

[slifty]

We sync Known Speakers with a google spreadsheet, but that spreadsheet is manually populated and therefore it has an unpredictable lag time behind claim review.

We should identify an approach for a more real-time (non manual) sync which also still allows for manual editing and cleanup.

[reefdog]

@cguess The source of truth here is FactStream's participants table, right? (cc also @emilyliu7321 who I think has actually been updating the Known Speakers sheet?)