By Saleh Salem and Estelle Shirbon GAZA/JERUSALEM (Reuters) – Water purifiers, medical supplies and tent poles are among items Israel has blocked from entering Gaza on aid trucks, according to an Egyptian Red Crescent document seen by Reuters and sources in Gaza, but Israel denied blocking any such items. Under a policy that long pre-dates the Oct. 7 Hamas attack on Israel and ensuing war in Gaza, Israel inspects trucks bound for the Palestinian enclave to stop any items it considers to have potential “dual use” – civilian or military. But the issue of which items do or don’t get through has b…