Toast pecans in a 350°F oven until fragrant, then cool completely.Beat cream cheese until smooth and fluffy.Add powdered sugar, vanilla, maple syrup, and salt, then mix well.Whip heavy cream in a separate bowl until soft peaks form.Gently fold whipped cream into the cream cheese mixture.Stir in most of the chopped pecans.Spread filling into prepared pie crust and smooth the top.Garnish with remaining pecans and chill for at least 4 hours before serving.