v3接口restful风格，规范化接口；添加mcp服务器；新增log模块

backend/services/llm_service.py

@@ -1,7 +1,11 @@
 import dashscope
 from http import HTTPStatus
 from backend.core.config import settings
+import logging
 
+# 获取当前模块的专用 Logger
+# __name__ 会自动识别为 "backend.services.crawler_service" 这样的路径
+logger = logging.getLogger(__name__)
 class LLMService:
     """
     LLM 服务封装层
@@ -21,10 +25,10 @@ class LLMService:
             if resp.status_code == HTTPStatus.OK:
                 return resp.output['embeddings'][0]['embedding']
             else:
-                print(f"[ERROR] Embedding API Error: {resp}")
+                logger.error(f"Embedding API Error: {resp}")
                 return None
         except Exception as e:
-            print(f"[ERROR] Embedding Exception: {e}")
+            logger.error(f"Embedding Exception: {e}")
             return None
 
     def rerank(self, query: str, documents: list, top_n: int = 5):
@@ -81,12 +85,12 @@ class LLMService:
                 
                 return reranked_results
             else:
-                print(f"[ERROR] Rerank API Error: {resp}")
+                logger.error(f"Rerank API Error: {resp}")
                 # 降级策略：如果 Rerank 挂了，直接返回粗排的前 N 个
                 return documents[:top_n]
                 
         except Exception as e:
-            print(f"[ERROR] Rerank Exception: {e}")
+            logger.error(f"Rerank Exception: {e}")
             # 降级策略
             return documents[:top_n]