Interface UnitProgress

interface UnitProgress {
    completedAt?: Date;
    completedLessons: number;
    lessons?: LessonProgress[];
    order: number;
    progressPercentage: number;
    startedAt?: Date;
    status: "completed" | "not_started" | "in_progress";
    timeSpent: number;
    totalLessons: number;
    unitId: string;
    unitTitle: string;
    unitType: "section" | "chapter" | "module";
}