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/pygments/styles/vs.py

@@ -0,0 +1,41 @@
+"""
+    pygments.styles.vs
+    ~~~~~~~~~~~~~~~~~~
+
+    Simple style with MS Visual Studio colors.
+
+    :copyright: Copyright 2006-2025 by the Pygments team, see AUTHORS.
+    :license: BSD, see LICENSE for details.
+"""
+
+from pygments.style import Style
+from pygments.token import Keyword, Name, Comment, String, Error, \
+     Operator, Generic
+
+
+__all__ = ['VisualStudioStyle']
+
+
+class VisualStudioStyle(Style):
+    name = 'vs'
+    
+    background_color = "#ffffff"
+
+    styles = {
+        Comment:                   "#008000",
+        Comment.Preproc:           "#0000ff",
+        Keyword:                   "#0000ff",
+        Operator.Word:             "#0000ff",
+        Keyword.Type:              "#2b91af",
+        Name.Class:                "#2b91af",
+        String:                    "#a31515",
+
+        Generic.Heading:           "bold",
+        Generic.Subheading:        "bold",
+        Generic.Emph:              "italic",
+        Generic.Strong:            "bold",
+        Generic.EmphStrong:        "bold italic",
+        Generic.Prompt:            "bold",
+
+        Error:                     "border:#FF0000"
+    }