📦 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/fast-glob/out/providers/transformers/entry.d.ts

@@ -0,0 +1,8 @@
+import Settings from '../../settings';
+import { EntryTransformerFunction } from '../../types';
+export default class EntryTransformer {
+    private readonly _settings;
+    constructor(_settings: Settings);
+    getTransformer(): EntryTransformerFunction;
+    private _transform;
+}

frontend/node_modules/fast-glob/out/providers/transformers/entry.js

@@ -0,0 +1,26 @@
+"use strict";
+Object.defineProperty(exports, "__esModule", { value: true });
+const utils = require("../../utils");
+class EntryTransformer {
+    constructor(_settings) {
+        this._settings = _settings;
+    }
+    getTransformer() {
+        return (entry) => this._transform(entry);
+    }
+    _transform(entry) {
+        let filepath = entry.path;
+        if (this._settings.absolute) {
+            filepath = utils.path.makeAbsolute(this._settings.cwd, filepath);
+            filepath = utils.path.unixify(filepath);
+        }
+        if (this._settings.markDirectories && entry.dirent.isDirectory()) {
+            filepath += '/';
+        }
+        if (!this._settings.objectMode) {
+            return filepath;
+        }
+        return Object.assign(Object.assign({}, entry), { path: filepath });
+    }
+}
+exports.default = EntryTransformer;