POST /api/admin/lesson-files now checks for an existing record with the
same (lessonId, name) before uploading — replaces it (old S3 object
deleted) instead of always creating a new one. Previously every save
cycle accumulated an extra copy; 1183 duplicates occupying 6.5 GiB were
found and cleaned up.
DELETE now receives the file URL and extracts the S3 key from it, so
manual deletion actually removes the object from storage.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
- Store human-readable label in LessonFile.name via optional label field on upload
- Add PATCH endpoint to rename existing files inline
- Admin: label input before upload, click-to-edit inline rename
- Student: colored format badge (PDF/DOCX/XLSX/ZIP/etc) replaces paperclip emoji
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>