The board patch read the work order version from the loaded list only. Once a
save moved the order out of that list (e.g. to another week), the next save,
Cancel or Complete from the open panel failed for lack of a version. The panel
now passes its server row as the fallback patch base.
Scope vendor and save toasts to successful assigned-vendor and slide-over saves.
Bind patch success callbacks per operation instead of shared mutate observers.