ROME — A day after Pope Benedict XVI stunned Roman Catholics by announcing that he would resign at the end of the month, the Vatican disclosed new details about his physical well-being on Tuesday, saying he had been fitted with a heart pacemaker a decade ago but that had not influenced his decision to become the first pope in almost 600 years to step down. The disclosure about the device, whose existence was not widely known, came as the Vatican grappled with a series of logistical questions raised by a decision that gave Benedict just 17 days to wind up...