There was a bug where if you created a slider, moved the last point, and then added a point such that it became a PerfectCurve, it would fail to recover after becoming a Bezier.
This fixes that.
Until now, API requests sent to dummy API were just lost in the void. In most cases this somehow worked as expected, but any logic which is waiting on a request to finish will potentially never get a response.
Going forward, I'm not 100% sure that every `Wait` on a web response will have local timeout logic (I think there is a certain amount of assumption that this is being managed for us by `APIAccess`), so I've made this change to better handle such cases going forward. Now, rather than nothing happening, requests will trigger a failure via the existing exception logic rather than silently pretending the request never arrived.