I've braced myself for ANY feedback you can send my way, so go ahead. :) I don't work to work on this in isolation.
I'm personally quite comfortable with the API so far, the only real doubts is error handling, i.e. IncTemperature from the PDF can optionally return an error and if that happens, it kills the session (state for an open browser tab) and restarts it with no state. Because errors need to be handled as regular state in LiveView. But it may be counterintuitive for Go developers. If anyone is interested, I can go into more details on this one.