docs: add comprehensive guide for Next.js 16 + Cloudflare (OpenNext) integration

[lora-sys]

📝 Summary
This PR introduces a detailed deployment guide for using Intlayer with Next.js 16 (App Router) on Cloudflare Workers via the OpenNext adapter. It addresses critical configurations required for Edge Runtime compatibility and React 19 hydration stability.
✨ Key Changes

• New Documentation : Added cloudflare-opennext.md (EN & ZH) covering:
  • Optimized middleware.ts matcher to reduce Edge Runtime overhead.
  • Correct nesting of IntlayerClientProvider with ThemeProvider for React 19.
  • Simplified wrangler.jsonc and build scripts to bypass mandatory R2 requirements.
• Website Integration : Updated docData.content.ts and home index.md to include the new section in the navigation tree. 🚀 Reference Implementation
  Successfully tested in a production-ready environment:

🚀 Reference Implementation

• Repo : lora-website
• Stack : Next.js 16.1.1, React 19, Intlayer 7.x, Cloudflare Workers. 💡 Future Suggestions (RFC)

💡 Future Suggestions (RFC)

1. Type Inference : Improve useIntlayer types to reduce manual .value access.
2. CLI Scaffolding : Add npx intlayer scan to auto-generate content templates.
   分支 (Branch): docs/cloudflare-opennext-guide