Add in-app WeChat scanning via Tencent iLink API: - server.js: QR code PNG renderer, WeChat API proxy, plugin auto-install - index.html: WeChat channel card with QR display and polling UI - Windows-Start.bat: auto-install WeChat plugin on startup - Windows-Install.bat: copy WeChat plugin during installation Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>