Fix variable name

src/handlers/sheets.go

@@ -112,7 +112,7 @@ func UploadSheet(c *gin.Context) {
 		FilePath:    filePath,
 		FileSize:    fileInfo.Size(),
 		FileHash:    fileHash,
-		ComposerID:  composer.Uuid,
+		ComposerId:  composer.Uuid,
 		CreatedAt:   time.Now(),
 		UpdatedAt:   time.Now(),
 	}