have DiscordState create a per-interaction temporary instance that has a sqlite connection arleady

[FoxLisk]

so instead of reaction handlers getting an Arc<DiscordState>, we'll call state.create_request_thingy() and that will, possibly among other things, grab a sqlite connection which we can then reuse everywhere

[FoxLisk]

actually, perhaps the best thing is to get the sqlite connection out of the discordstate entirely. some recent refactoring has made me really unhappy about the .diesel_cxn() method...