The files on the guard's legacy list build new WebServer(0, …) and read server.boundPort after start(), as sse-tile-grid-filter does. Files with several servers read each server's own port; quick-start's local helper lost its port parameter so the literal 0 sits where the server is built. Header comments that named a port say "ephemeral". No assertion changed except where it embedded the port.
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>