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/fastapi/responses.py

@@ -0,0 +1,48 @@
+from typing import Any
+
+from starlette.responses import FileResponse as FileResponse  # noqa
+from starlette.responses import HTMLResponse as HTMLResponse  # noqa
+from starlette.responses import JSONResponse as JSONResponse  # noqa
+from starlette.responses import PlainTextResponse as PlainTextResponse  # noqa
+from starlette.responses import RedirectResponse as RedirectResponse  # noqa
+from starlette.responses import Response as Response  # noqa
+from starlette.responses import StreamingResponse as StreamingResponse  # noqa
+
+try:
+    import ujson
+except ImportError:  # pragma: nocover
+    ujson = None  # type: ignore
+
+
+try:
+    import orjson
+except ImportError:  # pragma: nocover
+    orjson = None  # type: ignore
+
+
+class UJSONResponse(JSONResponse):
+    """
+    JSON response using the high-performance ujson library to serialize data to JSON.
+
+    Read more about it in the
+    [FastAPI docs for Custom Response - HTML, Stream, File, others](https://fastapi.tiangolo.com/advanced/custom-response/).
+    """
+
+    def render(self, content: Any) -> bytes:
+        assert ujson is not None, "ujson must be installed to use UJSONResponse"
+        return ujson.dumps(content, ensure_ascii=False).encode("utf-8")
+
+
+class ORJSONResponse(JSONResponse):
+    """
+    JSON response using the high-performance orjson library to serialize data to JSON.
+
+    Read more about it in the
+    [FastAPI docs for Custom Response - HTML, Stream, File, others](https://fastapi.tiangolo.com/advanced/custom-response/).
+    """
+
+    def render(self, content: Any) -> bytes:
+        assert orjson is not None, "orjson must be installed to use ORJSONResponse"
+        return orjson.dumps(
+            content, option=orjson.OPT_NON_STR_KEYS | orjson.OPT_SERIALIZE_NUMPY
+        )