📦 添加虚拟环境和启动脚本

新增:
- backend/venv/ - Python 虚拟环境
- backend/start.sh - 启动脚本（使用虚拟环境）
- backend/requirements.txt - 依赖列表
- .gitignore - 忽略虚拟环境和缓存文件

说明:
- 每个项目使用独立虚拟环境
- 避免依赖冲突
- 启动脚本自动创建和激活虚拟环境

frontend/node_modules/jsx-ast-utils/src/values/expressions/BindExpression.js

@@ -0,0 +1,24 @@
+/**
+ * Extractor function for a BindExpression type value node.
+ * A bind expression looks like `::this.foo`
+ * This will return `this.foo.bind(this)` as the value to indicate its existence,
+ * since we can not execute the function this.foo.bind(this) in a static environment.
+ *
+ * @param - value - AST Value object with type `BindExpression`
+ * @returns - The extracted value converted to correct type.
+ */
+export default function extractValueFromBindExpression(value) {
+  // eslint-disable-next-line global-require
+  const getValue = require('.').default;
+  const callee = getValue(value.callee);
+
+  // If value.object === null, the callee must be a MemberExpression.
+  // https://github.com/babel/babylon/blob/master/ast/spec.md#bindexpression
+  const object = value.object === null ? getValue(value.callee.object) : getValue(value.object);
+
+  if (value.object && value.object.property) {
+    return `${object}.${callee}.bind(${object})`;
+  }
+
+  return `${callee}.bind(${object})`;
+}