Pressing q/Ctrl+C in the TUI routes through SIGINT so the dashboard's
graceful shutdown runs (kills dev-server process groups, engines, mesh,
central-core). That shutdown awaits several teardown steps with no
timeout, so a single hung step left process.exit(0) unreachable: the
process never exited and the still-alive dashboard kept writing output
onto the restored shell. The shutdownInProgress guard also swallowed
repeat signals, so mashing q could not escape.
Both shutdown() and devShutdown() now arm an unref'd 3s hard-exit
watchdog on the first signal and force an immediate process.exit(0) on a
second signal.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
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