agent-session-kit 0.6.3

Fixed

• MCP sockets set SO_NOSIGPIPE on the server's listening and accepted
  file descriptors and on the stdio bridge's connect descriptor. A peer
  vanishing between poll and write used to raise SIGPIPE, killing the
  host process with no crash report — observed as a menu bar host's
  recurring silent exits. Writes to a gone peer now fail with EPIPE
  and run the ordinary teardown path. Hosts should still ignore
  SIGPIPE process-wide; this is defense in depth.