Log the ingot lot on every pour

Recording the alloy batch id on every trial and run row. When gas porosity turned up on two unrelated jobs in the same week, the shared ingot lot fell out of the data in about a minute.

Nothing, but only because the field was already there. Without it the investigation would have been a week of guessing.

The lot was quarantined and returned to the supplier. The whole case rests on a text field somebody bothered to fill in every time.