📦 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/emojis-list/README.md

@@ -0,0 +1,36 @@
+# emojis-list
+
+[![Dependency status](http://img.shields.io/david/Kikobeats/emojis-list.svg?style=flat-square)](https://david-dm.org/Kikobeats/emojis-list)
+[![Dev Dependencies Status](http://img.shields.io/david/dev/Kikobeats/emojis-list.svg?style=flat-square)](https://david-dm.org/Kikobeats/emojis-list#info=devDependencies)
+[![NPM Status](http://img.shields.io/npm/dm/emojis-list.svg?style=flat-square)](https://www.npmjs.org/package/emojis-list)
+[![Donate](https://img.shields.io/badge/donate-paypal-blue.svg?style=flat-square)](https://paypal.me/kikobeats)
+
+> Complete list of standard Unicode Hex Character Code that represent emojis.
+
+**NOTE**: The lists is related with the Unicode Hex Character Code. The representation of the emoji depend of the system. Will be possible that the system don't have all the representations.
+
+## Install
+
+```bash
+npm install emojis-list --save
+```
+
+## Usage
+
+```js
+const emojis = require('emojis-list')
+console.log(emojis[0])
+// => 🀄
+```
+
+## Related
+
+* [emojis-unicode](https://github.com/Kikobeats/emojis-unicode) – Complete list of standard Unicode codes that represent emojis.
+* [emojis-keywords](https://github.com/Kikobeats/emojis-keywords) – Complete list of am emoji shortcuts.
+* [is-emoji-keyword](https://github.com/Kikobeats/is-emoji-keyword) – Check if a word is a emoji shortcut.
+* [is-standard-emoji](https://github.com/kikobeats/is-standard-emoji) – Simply way to check if a emoji is a standard emoji.
+* [trim-emoji](https://github.com/Kikobeats/trim-emoji) – Deletes ':' from the begin and the end of an emoji shortcut.
+
+## License
+
+MIT © [Kiko Beats](http://www.kikobeats.com)