refactor: migrate dashboard to /dashboard and implement internal reverse proxy for gateway traffic

feat: enable iframe embedding by injecting a preload script to strip security headers and update CSP policies

feat: implement wa-guardian for automated WhatsApp pairing and add Control UI shortcut to dashboard

feat: implement DNS-over-HTTPS fallback for network requests and add a web dashboard to the health server.

Add MIT license and enhance README structure

Update README.md

Initial commit