SAN DIEGO — A hearing to determine if prosecutors in the “Fat Leonard” Navy bribery trial improperly withheld evidence has been postponed a day to give time for defense attorneys to continue to sift through hundreds of pages of discovery handed to them over the past few days. The discovery — mostly emails and messages — included new evidence indicating investigators received authorization to pay prostitutes up to $5,000 in “reward” money to come to San Diego to testify in the case. Five former U.S. naval officers are on trial, accused of taking bribes — including the services of prostitutes in…