By James Desborough Music superstar Katy Perry is walking away from American Idol for both professional and personal reasons – we can reveal. Perry will step down as judge after seven seasons as ABC bosses are not raising her pay packet of $30m and her hope to increase her family, claims an insider. Perry also plans to release a new album and perform live in the next couple of years, which would be curtailed by filming schedules. The fireworks star shocked fans on Monday’sJimmy Kimmel Live! when she announced her departure from the huge reality series. She said: “I think this probably will be …