- 업로드 시 HTML과 PDF를 별도 폴더에 저장 (/documents/, /pdfs/)
- 프론트엔드 필터링을 폴더 경로 기준으로 단순화
- PDF 삭제 시 외래키 참조 해제 로직 추가
- book-documents.js, book-editor.js 필터링 통일
- HTML 문서 목록에서 PDF 완전 분리
- Removed hierarchy view and integrated functionality into index.html
- Added book-based document grouping with dedicated book-documents.html page
- Implemented comprehensive multi-file upload system with drag-and-drop reordering
- Added HTML-PDF matching functionality with download capability
- Enhanced upload workflow with 3-step process (File Selection, Book Settings, Order & Match)
- Added book conflict resolution (existing book vs new edition)
- Improved document order adjustment with one-click sort options
- Added modular header component system
- Updated API connectivity for Docker environment
- Enhanced viewer.html with PDF download functionality
- Fixed browser caching issues with version management
- Improved mobile responsiveness and modern UI design
