DeletedAt struct represents the soft delete functionality in GORM.
It embeds the `gorm.DeletedAt` struct, which provides the necessary fields for soft deletion.
Delete updates the `Deleted` and `DeletedAt` fields of the `DeletedAt` object.
If `v` is true, `Deleted` is set to `v` and `DeletedAt` is set to the current time.
If `v` is false, `Deleted` is set to `v` and `DeletedAt` is set to `nil`.
IsDeleted returns true if the Deleted field of the DeletedAt object is set to true, indicating that the object has been deleted. Otherwise, it returns false.