Advance dialogue with Enter or Space

Dialogue has always advanced on a tap or a click, but a keyboard press on the focused dialogue didn't — pressing Enter or Space ran into an error instead of moving the conversation on, so the line never advanced and you were stuck until you reached for the mouse.

That's fixed. A keyboard press now counts as a plain 'next', so Enter or Space moves dialogue forward like any tap, and tapping or clicking still works exactly as before.