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/abap.py

@@ -0,0 +1,32 @@
+"""
+    pygments.styles.abap
+    ~~~~~~~~~~~~~~~~~~~~
+
+    ABAP workbench like style.
+
+    :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, \
+    Number, Operator
+
+
+__all__ = ['AbapStyle']
+
+
+class AbapStyle(Style):
+    name = 'abap'
+
+    styles = {
+        Comment:                'italic #888',
+        Comment.Special:        '#888',
+        Keyword:                '#00f',
+        Operator.Word:          '#00f',
+        Name:                   '#000',
+        Number:                 '#3af',
+        String:                 '#5a2',
+
+        Error:                  '#F00',
+    }