feat: add support for registering custom OpenAI-compatible providers via environment variables

feat: reduce default workspace sync interval to 180s and refactor sync logic into a dedicated function

feat: add UptimeRobot integration to prevent free Space sleep with automated monitor creation

feat: add optional WhatsApp integration with toggle and status monitoring

feat: migrate OPENCLAW_VERSION to build-time argument and hardcode health server ports

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.

Initial commit