Add /agents/ location block to nginx config to proxy agent heartbeat requests directly to backend API without /api/v1 prefix duplication, implement normalized_api_url helper to detect and fix double /api/v1 suffixes in agent config with automatic /api/v1 appending when missing, enhance heartbeat error logging to include HTTP status codes, response body preview, and resolved API URL for debugging connection
Add external_base_url helper to detect base URL from X-Forwarded-Host and X-Forwarded-Proto headers with fallback to request.base_url, replace hardcoded request.base_url usage in node_agent_install, node_agent_install_info, and public_node_agent_install endpoints to support reverse proxy deployments, update nginx config to pass X-Forwarded-Host header and use $http_host instead of $host for proper hostname forw