Each graceful-shutdown teardown step (dev servers, hybrid executor,
engine manager, peer exchange, mesh, central-core) now runs through
timeShutdownStep, which records the in-flight step name. A hang leaves
that name set, so the hard-exit watchdog reports the exact culprit on
stderr before force-exiting — no repro needed. Per-step timings print to
stderr under FUSION_DEBUG_SHUTDOWN=1; otherwise only steps slower than
1s are surfaced. Folds the per-step try/catch into the wrapper so a
throwing step logs and continues instead of stranding the process.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
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