Explore alternatives to constantly fetching entire election def for auth lib

[arsalansufi]

When an election definition is large, say, because it has a large seal, this seems to bog the system down.

Copying from Slack:

I know we're constantly refetching the election def from the store to pass to the auth lib. we initially planned to cache the relevant data in the auth lib, but as we all know caching is hard / error prone. and ultimately decided that the election def was too small for this to matter. a big seal definitely breaks that assumption. for the auth lib use case, all we really need is the election hash. we could explicitly persist that in the DB and just refetch that

Link to Slack thread: https://votingworks.slack.com/archives/C06H2PBP0MU/p1712798609099009?thread_ts=1712790170.563049&cid=C06H2PBP0MU