Crostini of Squid Stewed in Red Wine

Name: Crostini of Squid Stewed in Red Wine
Ingredients: 3 tablespoons extra-virgin olive oil, plus more for brushing; 2 garlic cloves, 1 halved and 1 pounded in a mortar or minced; 2 pounds cleaned small squid, bodies sliced 1/4 inch thick and large tentacles halved; Salt; 2 medium leeks, white parts only, thinly sliced; 1/4 teaspoon crushed red pepper; 2 teaspoons all-purpose flour; 1 medium tomato—peeled, seeded and finely chopped; 1 cup fruity, young red wine; Freshly ground black pepper; Sixteen 1/2-inch-thick slices French bread; 1/2 cup mayonnaise; Fresh lemon juice; 1 cup shredded arugula