chore(project): 初始化 React 项目并更新依赖配置

- 将项目从 Chrome 扩展模板迁移到 Create React App
- 移除原有的 Chrome 扩展相关文件(background.js、content.js、manifest.json)
- 删除旧的开发指南 DEVELOPMENT.md
- 更新 package-lock.json 以支持 React 开发环境
- 替换 .gitignore 文件内容为标准 React 项目忽略规则
- 移除所有原有的图标资源文件(images/*.png)
- 更新 README.md 为 Create React App 标准文档
- 添加 React、React DOM、React Router 等核心依赖
- 配置测试库(@testing-library)及相关工具
- 设置 web-vitals 性能监控依赖

package.json

@@ -1,19 +1,40 @@
 {
-  "name": "Chrome Extensions Gemini Demo",
-  "version": "1.1",
-  "type": "module",
-  "scripts": {
-    "build": "rollup -c",
-    "dev": "rollup -c -w"
-  },
+  "name": "chrome-extension-router-demo",
+  "version": "0.1.0",
   "private": true,
-  "devDependencies": {
-    "@google/generative-ai": "0.15.0",
-    "@rollup/plugin-commonjs": "^25.0.8",
-    "@rollup/plugin-json": "^6.1.0",
-    "@rollup/plugin-node-resolve": "^15.3.1",
-    "rollup": "4.22.4",
-    "rollup-plugin-livereload": "^2.0.5",
-    "rollup-plugin-serve": "^3.0.0"
+  "dependencies": {
+    "@testing-library/dom": "^10.4.1",
+    "@testing-library/jest-dom": "^6.9.1",
+    "@testing-library/react": "^16.3.1",
+    "@testing-library/user-event": "^13.5.0",
+    "react": "^19.2.3",
+    "react-dom": "^19.2.3",
+    "react-router-dom": "^6.30.2",
+    "react-scripts": "5.0.1",
+    "web-vitals": "^2.1.4"
+  },
+  "scripts": {
+    "start": "react-scripts start",
+    "build": "react-scripts build",
+    "test": "react-scripts test",
+    "eject": "react-scripts eject"
+  },
+  "eslintConfig": {
+    "extends": [
+      "react-app",
+      "react-app/jest"
+    ]
+  },
+  "browserslist": {
+    "production": [
+      ">0.2%",
+      "not dead",
+      "not op_mini all"
+    ],
+    "development": [
+      "last 1 chrome version",
+      "last 1 firefox version",
+      "last 1 safari version"
+    ]
   }
 }