feat(docs): update configuration and improve caching for documentation site

- Added Cloudflare and OpenNext configurations to .gitignore.
- Updated next.config.mjs to disable image optimization for better performance with CDN.
- Modified fetchJson function in github.ts to use 'force-cache' for improved data fetching efficiency.
- Updated multiple image assets for the documentation site.

apps/docs/next.config.mjs

@@ -5,6 +5,11 @@ const withMDX = createMDX();
 /** @type {import('next').NextConfig} */
 const config = {
   reactStrictMode: true,
+  images: {
+    // 站内图片均为已按展示尺寸截取的静态资源,直接由 CDN 提供,
+    // 避免在 Cloudflare Workers 上依赖运行时图片优化服务。
+    unoptimized: true,
+  },
 };
 
 export default withMDX(config);