fix(rag): fix pdfplumber concurrency issue and add debug logging

The pdfplumber parser now uses a global lock to prevent concurrent access issues during PDF image rendering. Additionally, added a warning log to trace knowledge retrieval results for debugging purposes. The syntax fix in knowledge node's match case ensures correct pattern matching behavior.

BREAKING CHANGE: The pdfplumber parser now requires LOCK_KEY_pdfplumber to be defined in sys.modules for thread safety.

Closes #841

api/app/services/draft_run_service.py

@@ -224,6 +224,7 @@ def create_knowledge_retrieval_tool(kb_config, kb_ids, user_id, citations_collec
             retrieve_chunks_result = knowledge_retrieval(query, kb_config)
             if retrieve_chunks_result:
                 retrieval_knowledge = [i.page_content for i in retrieve_chunks_result]
+                logger.warning(f"检索知识结果：{retrieval_knowledge}")
                 context = '\n\n'.join(retrieval_knowledge)
                 logger.info(
                     "知识库检索成功",