State file in root of data directory is created if collection fails to load

[LucasPickering]

If there's a collection parsing error, a default collection with an empty id is created. This means the database is created at ./data/state.sqlite (reduced from ./data//state.sqlite. Not sure the best way to handle this, but using an empty string as default state is not great. It should be more explicit about whether or not a collection is present. It would probably introduce a bunch of annoying checks in the view code, but that's the price of greatness 🤷