Delay productivity items until recipe completion

[alercah]

In FFF 309 it was mentioned that currently you don't get items back from crafting as discussed in this bug report. By changing recipes and thereby refunding ingredients after productivity has created one or more outputs, a player could use this to create additional products without consuming the ingredients.

Kovarex mentioned that a possible solution would be to only create productivity outputs when the recipe completes, but it would require additional memory and save space to store this on the assembler.

I have an alternate suggestion that may work if the code allows to solve this problem without additional space: allow the bonus_progress value on an assembler to exceed 1. Then, instead of creating an additional output when progress reaches 1 regardless of where crafting is in process, create outputs only on completion but possibly more than one at a time. So if, for instance, progress reaches 3.4 by the end of a craft, 3 bonus outputs are made and the progress is reset to 0.4.