Product picker: arrow keys, and no more phantom products

Pick products from the keyboard. In any product picker — submittals, estimates, POs, field materials — type to filter, ↑ / ↓ to move, Enter to link. The highlighted row now carries a brand-orange bar and tint, so there's no guessing which one Enter will grab.

No more phantom products. "+ New" and "+ Add Variant" used to save a blank product the moment you clicked. Close the drawer without saving and a stray "New Product" stayed in the catalog. Now nothing is saved until you hit Save Product — Cancel or close, and it's gone.