- Add src/lib/proxy-pool.ts: round-robin proxy pool that reads
proxy.txt (host:port:user:pass), tracks consecutive failures,
and rotates on threshold
- Integrate into src/index.ts: on fetch network error, mark proxy
as failed, rotate to next, and retry the request once
- proxy.txt loaded from PROXY_FILE/PROXY_LIST env var or ./proxy.txt
- Graceful no-op when proxy.txt doesn't exist (Vercel/Workers)
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>