namespace MetaCourse.Api.Entities; public class Topic { public Guid Id { get; set; } = Guid.NewGuid(); public string Title { get; set; } = string.Empty; public string? Description { get; set; } public int Position { get; set; } public Guid CourseId { get; set; } public Course Course { get; set; } = null!; public ICollection TopicResources { get; set; } = new List(); public ICollection UserProgresses { get; set; } = new List(); }