curl --location --request POST '/api/admin/books//files' \
--header 'Authorization: Bearer <token>' \
--header 'Content-Type: application/json' \
--data-raw '{
"languageId": 2,
"fileType": "pdf",
"sourceType": "google_drive",
"cloudUrl": "https://drive.google.com/file/d/abc123/view",
"fileName": "gc-fr.pdf",
"fileSizeBytes": 4718592
}'{
"id": "f2b3c4d5-e6f7-8901-bcde-f12345678901",
"fileName": "gc-fr.pdf"
}