Using a boolean argument just leads to a lot of trailing booleans in the
function calls and is not user friendly. Instead, introduce PostAction()
to send an action that runs after the coroutine (equivalent to passing
false or the default argument), and leave RunAction as the immediate
execution function.
1) More REPORTER, less exception processing
2) Remove UI calls from SPICE_MODEL
3) Don't replace netlist with errors; show both
4) Don't bail out of netlist generation after single error
Fixes https://gitlab.com/kicad/code/kicad/issues/14295