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/lexers/carbon.py

@@ -0,0 +1,95 @@
+"""
+    pygments.lexers.carbon
+    ~~~~~~~~~~~~~~~~~~~~~~
+
+    Lexers for the Carbon programming language.
+
+    :copyright: Copyright 2006-2025 by the Pygments team, see AUTHORS.
+    :license: BSD, see LICENSE for details.
+"""
+import re
+
+from pygments.lexer import RegexLexer, words
+from pygments.token import Text, Comment, Operator, Keyword, Name, String, \
+    Number, Punctuation, Whitespace
+
+__all__ = ['CarbonLexer']
+
+
+class CarbonLexer(RegexLexer):
+    """
+    For Carbon source.
+    """
+    name = 'Carbon'
+    url = 'https://github.com/carbon-language/carbon-lang'
+    filenames = ['*.carbon']
+    aliases = ['carbon']
+    mimetypes = ['text/x-carbon']
+    version_added = '2.15'
+
+    flags = re.MULTILINE | re.DOTALL
+
+    tokens = {
+        'root': [
+            (r'\n', Whitespace),
+            (r'\s+', Whitespace),
+            (r'\\\n', Text),
+            # comments
+            (r'//(.*?)\n', Comment.Single),
+            (r'/(\\\n)?[*].*?[*](\\\n)?/', Comment.Multiline),
+            # Declaration
+            (r'(package|import|api|namespace|library)\b', Keyword.Namespace),
+            (r'(abstract|alias|fn|class|interface|let|var|virtual|external|'
+             r'base|addr|extends|choice|constraint|impl)\b', Keyword.Declaration),
+            # Keywords
+            (words(('as', 'or', 'not', 'and', 'break', 'continue', 'case',
+                    'default', 'if', 'else', 'destructor', 'for', 'forall',
+                    'while', 'where', 'then', 'in', 'is', 'return', 'returned',
+                    'friend', 'partial', 'private', 'protected', 'observe', 'Self',
+                    'override', 'final', 'match', 'type', 'like'), suffix=r'\b'), Keyword),
+            (r'(self)\b', Keyword.Pseudo),
+            (r'(true|false)\b', Keyword.Constant),
+            (r'(auto|bool|string|i8|i16|i32|i64|u8|u16|u32|u64|'
+             r'f8|f16|f32|f64)\b', Keyword.Type),
+            # numeric literals
+            (r'[0-9]*[.][0-9]+', Number.Double),
+            (r'0b[01]+', Number.Bin),
+            (r'0o[0-7]+', Number.Oct),
+            (r'0x[0-9a-fA-F]+', Number.Hex),
+            (r'[0-9]+', Number.Integer),
+            # string literal
+            (r'"(\\.|[^"\\])*"', String),
+            # char literal
+            (r'\'(\\.|[^\'\\])\'', String.Char),
+            # tokens
+            (r'<<=|>>=|<<|>>|<=|>=|\+=|-=|\*=|/=|\%=|\|=|&=|\^=|&&|\|\||&|\||'
+             r'\+\+|--|\%|\^|\~|==|!=|::|[.]{3}|->|=>|[+\-*/&]', Operator),
+            (r'[|<>=!()\[\]{}.,;:\?]', Punctuation),
+            # identifiers
+            (r'[^\W\d]\w*', Name.Other),
+        ]
+    }
+
+    def analyse_text(text):
+        result = 0
+        if 'forall' in text:
+            result += 0.1
+        if 'type' in text:
+            result += 0.1
+        if 'Self' in text:
+            result += 0.1
+        if 'observe' in text:
+            result += 0.1
+        if 'package' in text:
+            result += 0.1
+        if 'library' in text:
+            result += 0.1
+        if 'choice' in text:
+            result += 0.1
+        if 'addr' in text:
+            result += 0.1
+        if 'constraint' in text:
+            result += 0.1
+        if 'impl' in text:
+            result += 0.1
+        return result