We need a way to run tests

[alecthomas]

Spitballing here.

There are two use cases:

1. Just being able to compile in order to run unit tests. We could potentially use a snapshot of a valid schema to achieve this.
2. Running integration tests.

For local tests we will still likely want resources like DBs to be usable.

For integration tests we could have something like an ftl test <dir> -- <test-command> command that combines ftl serve --recreate and ftl dev <dir>, then runs <test-command>, maybe.

[alecthomas]

I think we've half-arsed fixed this.