Lemon raspberry coconut cake

Recipe:

Cake:
2 ½ cups cake flour
1 tablespoon baking powder
½ teaspoon salt
1 ¼ cups whole milk or buttermilk
4 large egg whites
1 ½ cups sugar
2 teaspoons grated lemon zest
113g unsalted butter, at room temperature
½ teaspoon pure lemon extract

Buttercream:
1 cup sugar
4 large egg whites
340g unsalted butter, at room temperature
¼ cup fresh lemon juice (from 2 large lemons)
1 teaspoon pure vanilla extract

Finishing:
2/3 cup seedless raspberry preserves stirred vigorously or warmed gently until spreadable
About 1 ½ cups sweetened and shredded coconut