Adds optional FIRECRAWL_API_URL environment variable to support self-hosted Firecrawl deployments alongside the cloud service. - Add FIRECRAWL_API_URL to optional env vars in hermes_cli/config.py - Update _get_firecrawl_client() in tools/web_tools.py to accept custom API URL - Add tests for client initialization with/without URL - Document new env var in installation and config guides