SAN JOSE, Calif. — A woman and man stockpiled diapers and baby formula, got a child’s rocker and hatched a plan to abduct her friend’s three-month-old grandson, sparking a frantic search that garnered national attention earlier this week, according to prosecutors. But even after the pair were arraigned Thursday, questions remained about why they wanted to kidnap the child in the first place. San Jose residents Yesenia Guadalupe Ramirez, 43, and Jose Roman Portillo, 28, were charged with conspiracy to commit a felony, kidnapping a child under the age of 14 and first-degree burglary — all feloni…