v3.0 MAX LEVEL: multi-AI fallback, self-healing, voice, admin, rate-limit, smart routing

Add multi-model Gemini fallback + z-ai chat fallback for 24/7 resilience

v2.0: Gemini AI for chat + z-ai for search/image, robust error handling

Add ca-certificates, health server, and Telegram API retry logic

Switch to webhook mode for HF Spaces compatibility

Add Telegram API timeout handling and keepAlive agent

Add z-ai-config for ZAI SDK

Initial: Telegram agentic chat bot