Three issues prevented --engine lightpanda from working with official
Lightpanda release builds:
1. Missing --log_level info: Lightpanda release builds default to
log_level=warn, which suppresses the info-level "server running"
startup message. wait_for_address() blocks forever reading an empty
stderr pipe. Pass --log_level info explicitly.
2. --timeout 0 means instant disconnect: Lightpanda interprets 0 as
"timeout after 0ms", not "no timeout". Use 604800 (1 week, the
documented maximum) instead.
3. extract_address only matched pretty format: Release builds use
logfmt (address=HOST:PORT without spaces), but the parser only
matched the pretty format (address = HOST:PORT with spaces). Handle
both formats.
