feat: 修改 find_available_ocr_files_multi_source 函数，简化数据源唯一标识生成逻辑

ocr_validator_utils.py

@@ -823,7 +823,7 @@ def find_available_ocr_files_multi_source(config: Dict) -> Dict[str, List[Dict]]
     for source in config.get('data_sources', []):
         source_name = source['name']
         ocr_tool = source['ocr_tool']
-        source_key = f"{source_name}_{ocr_tool}"  # 创建唯一标识
+        source_key = f"{source_name}"
         
         ocr_out_dir = source['ocr_out_dir']