chore: 添加虚拟环境到仓库

- 添加 backend_service/venv 虚拟环境
- 包含所有Python依赖包
- 注意：虚拟环境约393MB，包含12655个文件

backend_service/venv/lib/python3.13/site-packages/chromadb/utils/fastapi.py

@@ -0,0 +1,18 @@
+from uuid import UUID
+from starlette.responses import JSONResponse
+
+from chromadb.errors import ChromaError, InvalidUUIDError
+
+
+def fastapi_json_response(error: ChromaError) -> JSONResponse:
+    return JSONResponse(
+        content={"error": error.name(), "message": error.message()},
+        status_code=error.code(),
+    )
+
+
+def string_to_uuid(uuid_str: str) -> UUID:
+    try:
+        return UUID(uuid_str)
+    except ValueError:
+        raise InvalidUUIDError(f"Could not parse {uuid_str} as a UUID")