Grilled Zucchini Boats with Lemony Tabbouleh

Name: Grilled Zucchini Boats with Lemony Tabbouleh
Ingredients: 1/2 cup bulgur wheat; 1/2 cup boiling water; 2 medium lemons; 1 small plum tomato; 1 medium Persian cucumber; 1 medium scallion; 1/2 bunch fresh parsley; 1/2 bunch fresh mint; 4 tablespoons olive oil, divided; 1 3/4 teaspoons kosher salt, divided, plus more as needed; 1/4 teaspoon ground cardamom; 1/4 teaspoon ground cumin; 1/8 teaspoon freshly ground black pepper, plus more as needed; 1 clove garlic; 6 medium zucchini (about 8 ounces each); 8 ounces lean ground beef or plant-based ground beef substitute; 2 tablespoons ras el hanout; 1/4 cup plain Greek yogurt