Cook pasta to desired doneness as directed on package adding 1 teaspoon salt to cooking water. Drain; cover to keep warm.
Meanwhile, heat oil in 12-inch skillet over medium heat until hot. Add onion and carrots; cook 3 minutes, stirring frequently. Add broth and lemon juice; cook 3 to 4 minutes or until mixture boils. Reduce heat to medium-low; add tuna. Cook 2 minutes, stirring occasionally. Add sugar snap peas; cook an additional 4 to 6 minutes or until carrots and peas are crisp-tender, stirring occasionally. Stir in dill and lemon-pepper seasoning.
Place pasta in individual serving bowls. Top each serving with tuna mixture.