Refactored DB to be Series->Volumes->Chapters instead. All functionality that previously worked still works. Cleanup still needed.

API/Data/BookmarkDto.cs

@@ -3,6 +3,7 @@
     public class BookmarkDto
     {
         public int VolumeId { get; init; }
+        public int ChapterId { get; init; }
         public int PageNum { get; init; }
         public int SeriesId { get; init; }
     }