Place vinegar and shallot in a bowl; let stand 10 minutes. Add mustard, pepper, 3 tablespoons of the oil, and 1/4 teaspoon of the salt to bowl; whisk until well combined.
Heat a large nonstick skillet over medium. Add remaining 1 teaspoon oil; swirl to coat. Add eggs; cook until whites are set, 1 to 2 minutes. Turn over; cook 1 minute for runny yolks. Sprinkle with remaining salt.
Divide spinach among 4 plates. Top each with 1 egg, 2 tablespoons goat cheese, 2 tablespoons blueberries, and 1 tablespoon pumpkin seeds. Drizzle with vinaigrette.
