mixed apples, such as Granny Smith or Macintosh, peeled, cored, and cut into ½-inch wedges (about 8 medium apples) • cup/300 grams packed dark brown sugar, divided • ground cinnamon • fresh lemon juice • cups/180 grams all-purpose flour • tablespoons/170 grams unsalted butter, melted, plus more for buttering the pan • cup/80 grams old-fashioned rolled oats • cup/113 grams pecans, chopped • kosher salt