feat(multimodal): support document image extraction and inline vision processing

Added document image extraction capability for PDF and DOCX files, including page/index metadata and storage integration. Extended `process_files` with `document_image_recognition` flag to conditionally enable vision-based image processing when model supports it. Updated knowledge repository and workflow node logic to enforce status=1 checks. Added PyMuPDF dependency.

api/app/services/workflow_service.py

@@ -694,7 +694,8 @@ class WorkflowService:
             "nodes": config.nodes,
             "edges": config.edges,
             "variables": config.variables,
-            "execution_config": config.execution_config
+            "execution_config": config.execution_config,
+            "features": feature_configs
         }
 
         try:
@@ -894,7 +895,8 @@ class WorkflowService:
             "nodes": config.nodes,
             "edges": config.edges,
             "variables": config.variables,
-            "execution_config": config.execution_config
+            "execution_config": config.execution_config,
+            "features": feature_configs
         }
 
         try: