“Nilüfer Yanya is a 21-year-old Londoner who makes smoky, soothing pop songs that are simple in their delights yet confounding in their clever construction. There are a few reference points for what she does—her sneaky guitar skills suggest Mary Timony and Helium, and her cool dance melodies recall the xx—but she’s pretty special all her own. “Sliding Doors,” a cut from her upcoming Plant Feed EP, ”