Special HQ set up for ceremony, whose date is still undetermined, nearly three months after supreme leader was killed by Israel in war’s opening salvo TEHRAN, Iran — Iranian authorities are laying the groundwork for a “grand” funeral for slain supreme leader Ayatollah Ali Khamenei, official media reported Friday, following a lengthy postponement due to the Islamic Republic’s war with the United States and Israel. Though the timing was still uncertain, “a special headquarters has been formed to prepare for the funeral ceremony, and various agencies are currently planning and making arrangements,” state TV reported, citing Mohsen Mahmoudi, head of the Tehran Coordination Council for Islamic Propaganda. Khamenei, who led the Islamic Republic for more than three decades, was killed in the first wave of US-Israeli strikes that launched the war on February 28. His son and successor Mojtaba Khamenei was also wounded in the attacks and has not been seen in public since assuming office.…