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/yarl/_quoting.py

@@ -0,0 +1,19 @@
+import os
+import sys
+from typing import TYPE_CHECKING
+
+__all__ = ("_Quoter", "_Unquoter")
+
+
+NO_EXTENSIONS = bool(os.environ.get("YARL_NO_EXTENSIONS"))  # type: bool
+if sys.implementation.name != "cpython":
+    NO_EXTENSIONS = True
+
+
+if TYPE_CHECKING or NO_EXTENSIONS:
+    from ._quoting_py import _Quoter, _Unquoter
+else:
+    try:
+        from ._quoting_c import _Quoter, _Unquoter
+    except ImportError:  # pragma: no cover
+        from ._quoting_py import _Quoter, _Unquoter  # type: ignore[assignment]