If it hadn’t been music, somewhere in the arts’ more confronting and shadowed realm would have pulled Ian Curtis to its introspective ruin one way or another. “I used to work in a factory, and I was really happy because I could daydream all day,” he once confessed to NME. If punk and popular music hadn’t zapped its formative lightning on the young Macclesfield teen, it’s easy to imagine a future in literature or the fine arts; such were his evoc…