feat: Add changelog component and styling

- Install vite-plugin-markdown for parsing markdown files
- Add Changelog component to WelcomeModal
- Implement changelog-related styles in app.css
- Update vite config to use markdown plugin
- Declare .md module type in vite-env.d.ts
- Minor code cleanup in WelcomeModal component

CHANGELOG.md

@@ -0,0 +1,8 @@
+### 2024-10-08
+- 增加 更新日志 显示
+
+### 2024-10-07
+- 优化 **OpenCV.js** 库加载、使用 `cdn.jsdmirror.com` 替换 `jsdelivr.net`
+- **Pikafish** 使用 `xiangqiai.com` 的 wasm 版本
+- 优化黑棋子识别
+- 新增欢迎提示和加载界面

package.json

@@ -20,7 +20,8 @@
     "@preact/preset-vite": "^2.9.1",
     "typescript": "^5.6.2",
     "vite": "^5.4.8",
-    "vite-plugin-cdn2": "^1.1.0"
+    "vite-plugin-cdn2": "^1.1.0",
+    "vite-plugin-markdown": "^2.2.0"
   },
   "packageManager": "[email protected]",
   "homepage": "https://ifwu.github.io/xiangqi-analysis/",