Write more Go tests

Now that go things are back in this repository and the bindings are mostly updated, we should write more tests to verify they work.

We don't need to replicate what is already tested in quark-test, but we need enough to verify that the boundary between C<>Go is correct, this means a simple test for each kind of event is likely enough.

Start by inspecting the Go bindings and the existing coverage in quark-test, then identify the event kinds exposed across the C<>Go boundary. Add focused tests for each event kind without duplicating quark-test coverage; done means the bindings' event boundary behavior is verified.

Written by the indexing model from the issue text.