Heat 1 teaspoon olive oil in a skillet over medium-high heat.
Cut the chicken into bite-sized pieces and season with salt, freshly ground black pepper, and 1/2 teaspoon garlic powder.
Sauté the chicken in the hot skillet for about 5–7 minutes, stirring occasionally, until cooked through and no longer pink inside; transfer to a bowl to cool slightly.
In a large bowl, combine the cooked chicken, 1/4 cup diced celery, 1/2 cup diced red onion, 1/2 cup halved grapes, 1/2 cup diced apple, 1/4 cup dried cranberries, and 1/4 cup chopped almonds.
In a small bowl, whisk together 1/3 cup plain Greek yogurt, 2 tablespoons mayonnaise, and 1 teaspoon lemon juice until smooth.
Pour the dressing over the chicken mixture and toss gently to coat; season with additional salt and pepper to taste.
Wash and pat the lettuce leaves dry, then spoon a generous portion of the chicken salad into each leaf and serve as wraps.