📦 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/eslint-plugin-import/docs/rules/no-webpack-loader-syntax.md

@@ -0,0 +1,39 @@
+# import/no-webpack-loader-syntax
+
+<!-- end auto-generated rule header -->
+
+Forbid Webpack loader syntax in imports.
+
+[Webpack](https://webpack.js.org) allows specifying the [loaders](https://webpack.js.org/concepts/loaders/) to use in the import source string using a special syntax like this:
+
+```js
+var moduleWithOneLoader = require("my-loader!./my-awesome-module");
+```
+
+This syntax is non-standard, so it couples the code to Webpack. The recommended way to specify Webpack loader configuration is in a [Webpack configuration file](https://webpack.js.org/concepts/loaders/#configuration).
+
+## Rule Details
+
+### Fail
+
+```js
+import myModule from 'my-loader!my-module';
+import theme from 'style!css!./theme.css';
+
+var myModule = require('my-loader!./my-module');
+var theme = require('style!css!./theme.css');
+```
+
+### Pass
+
+```js
+import myModule from 'my-module';
+import theme from './theme.css';
+
+var myModule = require('my-module');
+var theme = require('./theme.css');
+```
+
+## When Not To Use It
+
+If you have a project that doesn't use Webpack you can safely disable this rule.