By  Michael Levitt Lebanon has lost one of its most beloved artists, the playwright and musician Ziad Rahbani. SARAH MCCAMMON, HOST: Lebanon this week mourned the passing of one of its most beloved artists. Musician and playwright Ziad Rahbani died a week ago. NPR’s Michael Levitt has this remembrance. (SOUNDBITE OF ZIAD RAHBANI SONG, “ANA…