One-click setup script

[TomGranot]

Bulletproof setup script that handles:

1. Prerequisites check (Node.js, container runtime)
2. Dependency installation
3. Container image build
4. .env configuration (API key)
5. WhatsApp QR code auth (interactive)
6. Service installation (launchd/systemd)
7. Verification test

Reduce setup from ~30 manual steps to ~5 interactive steps.