[thinhnx128]

Summary

Implements graceful shutdown (SIGTERM, SIGINT, SIGHUP) and automatic zombie worker / orphaned temporary directory reaping for EdgeChains worker processes:

Key Changes

1. JS/wasm/sync-rpc/index.js — Active Worker Registry & Two-Phase Reaper:
   • Tracks spawned worker child processes in activeWorkers and installs idempotent signal handlers (exit, SIGINT, SIGTERM, SIGHUP).
   • Performs a two-phase teardown (SIGTERM followed by SIGKILL escalation after 1.5s if the worker remains hung) so background workers are never left orphaned holding TCP ports.
   • Passes EDGECHAINS_PARENT_PID to the child worker.
2. JS/wasm/sync-rpc/worker.js — Parent Liveness Watchdog & Graceful Server Drain:
   • Polls parent liveness via process.kill(parentPid, 0) every 1s and triggers gracefulShutdown(0) if the parent process dies unexpectedly.
   • Adds SIGINT / SIGTERM handlers and a "shutdown" command that drains active connections via server.close() before exiting, while binding to loopback (127.0.0.1).
3. JS/edgechains/arakoodev/src/sync-rpc/lib/sync-rpc.ts — Automatic Temp Directory Cleanup:
   • Registers sync-rpc-* temporary directories in activeTempDirs and cleans them up on process exit/signals (fs.rmSync(dir, { recursive: true, force: true })), plus exposes syncRPC.dispose().

[thinhnx128]

I have read the Arakoo CLA Document and I hereby sign the CLA

[thinhnx128]

Closing this to reduce review load — it wasn't requested by the maintainers. Thanks for your time; happy to reopen if it's useful.